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Duplex loads Help needed

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Topic: Duplex loads Help needed
Posted By: 8shots
Subject: Duplex loads Help needed
Date Posted: June/25/2007 at 07:43

Does anyone have experience with duplex loads? Mixing fast burning and slow burning powder to obtain a more efficient one for a particular rifle?

I have read an article which advocates the mixing of a slower burning powder at 40% by weight and a faster burning powder as the balance. The article states do not mix the powder before weighing, which makes sense. It further states "place the slower burning powder on top of the primer, followed by the faster burning powder". The question now arises, should one fill the shell with dacron to prevent mixing in the shell, or can mixing take place in the shell?

The idea behind this is to give good speeds with good bullet stability.

Any information or advice will be welcome.




Replies:
Posted By: Dale Clifford
Date Posted: June/25/2007 at 08:44

duplex loads are not recommended by anyone who cares for the people they associate. unless you have the safety equipment a spare duplicate of the firearm and say an Oheler ballistic lab (pressure equipment)

 

duplex loads belong to the era of steel screw on webs, for higher pressure, brass weld primer tubes to bring the flame front to the "top" of the powder charge,

 

if they worked, you can bet competitive long range shooters, would have developed the protocols long ago.

first time I was made aware of duplexing was in the 60's and it hasn't gone anywhere since.,

 

 

 



Posted By: 8shots
Date Posted: June/25/2007 at 09:26

Thanks Dale. Then another question. If I am getting a better grouping as I lower the velocity (from 2800fps to 2400fps) on a 308 cal 200gr, would there theoretically (or practically) be a speed beyond 2800fps where the grouping starts to improve again?

As for the duplex load, we have S365 and S385, both recommended for the 300H&H, but the S365 is hotter then your IMR4831 and our S385 is slower again, the claim being that the above can duplicate your IMR4831.



Posted By: Dale Clifford
Date Posted: June/25/2007 at 09:31

duplexing experiments in the us -- involve a blast shield and something like 4350 and 10 grs unique. yes a higher velocity can give a more accurate load, this is seen especially in varmint guns.



Posted By: pyro6999
Date Posted: June/25/2007 at 19:50
sounds crazy to me kids

-------------
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"


Posted By: Dale Clifford
Date Posted: June/25/2007 at 22:33
maybe -- but triplexing is really nuts.


Posted By: pyro6999
Date Posted: June/26/2007 at 06:24
yeah its the stuff they end up using to make a nuke i think

-------------
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"


Posted By: hot30
Date Posted: June/26/2007 at 22:20

8shots, if you insist to persue the duplex loads, snuggle-up with someone from the loading division of a powder and ammo manufacturer..  I shoot my .308 with 45gr of 4350 and Dont try the unique mixer.!!!!!  Bribe your chemist for the rest.

 

       Sorry Dale, but your correct about blast shields etc. if you DO play with unique



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30


Posted By: 8shots
Date Posted: June/27/2007 at 02:30

Thanks for all your words of caution. Playing with this stuff is dangerous.

The duplex load that I am pursuing is using two excisting powders, both which are safe in my 300H&H. The one being S385 which burns slow, and using S365, which burns slightly faster. The maximum load of neither is exceeded. The idea is to use 40% S385 and 60%S365. This should give a slightly more efficient burn in the rifle according to the fundis.

I have taken this up with our powder manufactures, and allthough they cannot endorse it for obvious reasons, they are not concerned that I will blow myself up.

 



Posted By: pyro6999
Date Posted: June/27/2007 at 06:07
Originally posted by hot30 hot30 wrote:

8shots, if you insist to persue the duplex loads, snuggle-up with someone from the loading division of a powder and ammo manufacturer..  I shoot my .308 with 45gr of 4350 and Dont try the unique mixer.!!!!!  Bribe your chemist for the rest.

 

       Sorry Dale, but your correct about blast shields etc. if you DO play with unique

 

oh the stories my old man tells about garbage cans and other steel containers and unique powder.



-------------
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"


Posted By: 8shots
Date Posted: June/27/2007 at 10:23

I have made up two rounds on the 40% 60% formula. As we have no blast shields available, I will ask my best buddy to take the first shot. If there are no further postings then you know it was a bad idea!

PS What is unique powder?



Posted By: Bigdaddy0381
Date Posted: June/27/2007 at 10:29

 8shots

 just tie the gun to a tree stand way way back and pull trigger with string. then have your best buddy fire second shot.



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: Dale Clifford
Date Posted: June/27/2007 at 11:06

unique is a med. HANDGUN powder---   plexing was really popular back in the 80's when the guys used to put the guns in old truck tires and fire them with a string from afar. (really -no sh*t)  of course most of the guns were reworked miliary surplus- but none the less.

reminds when I used to talk the neighbor kid into holding on to a pipe while I stuffed an old CC battery and M-80 into it. --- good for about 400 yds.



Posted By: Bigdaddy0381
Date Posted: June/27/2007 at 11:16

  cc battery  awsome.

 

  when i was younger ( lol ) we would take a bowling ball and drop it from 700 or so feet and see if we could hit a car that we parked at the end of the strip to see if we can even hit it. we did once but it wasen't the right car.we hit my buddies wifes car about 100 yards away in there drive way. it smashed it pretty good.we wound up just sticking to sticks of dynomite under the one we should have it and blew it up around midnight that night.we had ever cop withen 20 miles visiting us.

 

It is amazing what wild turkey and friends with out good since will make you do.

 

if i mail someone a pic can they shrink it and add it for me.It was from a few weekends ago.

 

 



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 8shots
Date Posted: June/27/2007 at 13:35
As kids we used to take a half inch galv waterpipe and weld one end shut. A big bang cracker and a marble fitted exactly. This thing would shoot right through a door. Ask my brother, he knows!


Posted By: hot30
Date Posted: June/27/2007 at 13:47
The "string thing".   Just before you pull the string you still half s--t yourself.. Doesnt matter how many times you do this, ya dont get used to it!!

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30


Posted By: hot30
Date Posted: June/27/2007 at 13:53
Bigdaddy,  I grew up in the snow belt.  Wait until the snow gets allittle wet  and roll your snowball  down a 4 or 500 ft steep grade.  Time it so ya know who your going to knock off the road though..  After your done kicking the snot out of each other, then its a good laugh..

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30


Posted By: 8shots
Date Posted: June/27/2007 at 14:55

 

You guys were right, you don't play with unique!!!

 

 



Posted By: Dale Clifford
Date Posted: June/27/2007 at 14:59

The "string thing".   Just before you pull the string you still half s--t yourself.. Doesnt matter how many times you do this, ya dont get used to it!!

 

 

 

I know the neighbor kid did!!!!!!



Posted By: Mike McDonald
Date Posted: June/27/2007 at 19:55
I made nitroglyceryn one time when I was 12 or so.

I'd rather do it again compared to playing witha duplex load in a rifle.


Posted By: Dale Clifford
Date Posted: June/27/2007 at 20:31
gee whats a little hot sulfuric and nitric acid compared to a 6lb grenade frag.


Posted By: pyro6999
Date Posted: June/27/2007 at 20:38
you know i was asking a friend of mine who is older than me by more than 10 yrs if he had heard of the whole duplexing thing and he told me he's very sure that a lot of the gun powders on the market today already are duplexed, we both agreed that there isnt really any need to try such a dangerous practice with the huge versitile lineup of gun powders we have today he said in the 50's and 60's we didnt have sh*t for powder compared to half the stuff we have today so yeah back  then sometimes you would do it to get a desired result, and unless your a pretty good chemist your liable to end up missing limbs fingers eyes  oh maybe your house and your next door neighbors.

-------------
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"


Posted By: 8shots
Date Posted: June/28/2007 at 08:23

OK, I made it! I have tested the following loads this morning (all at 89,5mm OAL) with 200gr Nosler Part.

67 gr S385 The max the manuf recoomend, which should give 2750 fps

67,5 gr S385

68gr S385

60 gr with 40% S385 and on top 60% S365 held down by toilet paper.

Two fouling shots with 165gr Spartan bullet.

 

The following interesting facts emerged:

The 68 gr gave the best group indication with 1/2 inch grouping.

The rifle seems to throw one bullet centre high, one centre right and so it continues. The two fouler shots did not do this. It could be that I am flinching on each second shot. I shoot two, mark them and shoot the next two. The rifle has a solid kick on these loads. The trigger is also still an issue.

The one shot of 111 was pulled. That was the first of the 111.

The duplex load gave a nice recoil feel to the rifle, very smooth.

Toilet paper in front of 60gr of powder gives a nice snowfall effect!!

 

I will be hunting again on 6 Jul and will stick with 68gr S385 behind a 200gr Nosler Part with OAL at 89,5mm.

Bring on the big bulls!



Posted By: Dale Clifford
Date Posted: June/28/2007 at 10:38

a lot of powders today are double based, nitrocellulose , and nitro so technically they are duplex-- the older slang term has a different meaning however.  a smart chemist never, never, plays with anything with more than 2 oxygen molecules in concentrations greater than .0001.

a short time after the duplex craze, there were some people selling "inhibitors" which when sprayed on a fast index powder, slowed the index.

as hot30 puts it-- the "pucker" factor is just to high



Posted By: 8shots
Date Posted: June/28/2007 at 10:46

Thanks for your words of caution. Maybe that is why someone suggested I use toilet paper in stead of Dacron as a filler!!!

I will just stick with the single powder loads.



Posted By: 303Guy
Date Posted: September/02/2007 at 13:59
Originally posted by 8shots 8shots wrote:

Does anyone have experience with duplex loads? Mixing fast burning and slow burning powder to obtain a more efficient one for a particular rifle?.......

The idea behind this is to give good speeds with good bullet stability.

Any information or advice will be welcome.

 

Hi there 8shots. 

  I can only say yes and no.  Yes, because I did it for the first time yesterday.  It sounds like you are in my old country.  Ok, like the others have said,  DO NOT USE DOUBLE BASE POWDERS!  And do use plenty of caution.

   My experiments were with two rifle powders.  My theory was that if my AR2205(H4227)  -  close to MP300 - was topping out with heavier bullets at a cirtain load, then by reducing an amount of that powder and replacing the volume with a slower powder AR2208(Varget)  -  close to MR200 - then I would lower the pressure.  I started by replacing about 10% AR2205 with AR2208 and ended up with a charge of 60% AR2205 and 40% AR2208.  I weighed the AR2205 - placed it into the case then filled the remaining space with AR2208. I then poured that out, mixed it and put it back in.  That left more space as the spaces between the larger granules filled with the smaller ones, so I added more AR2208 untill the case was full enough to slightly compress the powder.  The idea was to prevent segregation of the two powders from shaking.  I did all my test firing into a firing tube with damp sand in the trap at the bottom.  The only velocity indicator I had was the degree of disintegration of the bullet.  The final load gave me total lead loss.  This showed that the final velocity achieved is way higher than with AR2205 alone.  At all times, I was checking for pressures and at all times, pressure signs were LESS than with the top AR2205 load.

 

A bit long-winded here - sorry about that!

 

My objective?  To stabilize a 55gr bullet in my hornet!

 

 



-------------
Regards
303Guy


Posted By: 8shots
Date Posted: September/03/2007 at 09:33

Hi 303Guy,

I live and hunt in South Africa. Thanks for sharing your experience on duplex loads. The recipe I tried also worked and certainly the recoil felt less severe then on other loads. Obviously this is very unscientific and the only factor I measured was grouping/accuracy.

I have however found a straight load that works, and quite frankly I cannot see myself measuring out two loads for each round. Way too time consuming! But an interesting concept never the less.



Posted By: 303Guy
Date Posted: September/05/2007 at 13:48

Hi  8shots

 

I was from the old Natal - Pietermaritzburg and Zululand before that.  I am in New Zealand now.  Our hunting is a little bit wetter than yours!

 

You are right about the effort!  I can measure the one powder but have to weigh the other.  I can use Lil'Gun to achieve the same end - which I will.  But is was fun.

 

Regards

303Guy

 



-------------
Regards
303Guy


Posted By: Dale Clifford
Date Posted: September/05/2007 at 14:23
you guys are crazy-- orginal duplexing gave a lot of emphazise to maximize segregation


Posted By: 303Guy
Date Posted: September/06/2007 at 02:48
Originally posted by 8shots 8shots wrote:

......

PS What is unique powder?

 

Hi 8shots

 

I didn't see whether anyone answered you.  It very similar to MP200 - small pistol powder.  It is a double base powder containing nitro-glycerine.  In duplex loads, it was used as a 'primer' to ignite slower powders in magnum cases.  That is dangerous territory!  But it can used to clean up black powder cartridges, although I think they use shotgun powders like Bullseye - similar to MS200.



-------------
Regards
303Guy


Posted By: 303Guy
Date Posted: September/06/2007 at 02:59

Originally posted by Dale Clifford Dale Clifford wrote:

you guys are crazy-- orginal duplexing gave a lot of emphazise to maximize segregation

 

If I wasn't crazy, I would go insane!

 

Hi Dale

 

You are right.  Those guys were using double base powders to ignite single base powders.  They were crazy!  And bold.  I believe some of them lived.

 

What we tried was substituting some of the 'normal' charge of a fast rifle powder with a quantity of slower rifle powder to reduce pressures and/or increase velocity without raising pressures.  I seriously don't think it to be any more dangerous than reloading itself - which is dangerous.  Not as dangerous as driving a car 'though.



-------------
Regards
303Guy


Posted By: pyro6999
Date Posted: September/06/2007 at 16:55
lets try bullseye and r-25!!

-------------
They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead"

343 we will never forget

God Bless Chris Ledoux
"good ride cowboy"


Posted By: Dale Clifford
Date Posted: September/06/2007 at 21:18

What we tried was substituting some of the 'normal' charge of a fast rifle powder with a quantity of slower rifle powder to reduce pressures and/or increase velocity without raising pressures.

 

oh I understand the theory alright, the same reason I used to dip M-80's in epoxy and get the neighbor kid to light them off. or I think I'll smooth out the irregularties in the extreme spread in this lot of varget with soem 4350.



Posted By: 303Guy
Date Posted: September/07/2007 at 02:43

Originally posted by Dale Clifford Dale Clifford wrote:

....... orginal duplexing gave a lot of emphazise to maximize segregation

 

I just couldn't stop while I was still ahead!  I just had to try segregating the powders.  I first loaded up a test with the slower powder first.  Less pressure, so I tried the slower powder last.  Still low pressures but the partially burned powder kernels have a massive kinetic energy!  I kept the powders separate by compressing the load.

 

So it seems that maximum pressures are achieved by mixing the two powders.

 

Just for the record - I am NOT promoting this practice.  It CAN be dangerous!  It is in any case, just way too much trouble.

 



-------------
Regards
303Guy


Posted By: 303Guy
Date Posted: September/07/2007 at 02:50

Originally posted by pyro6999 pyro6999 wrote:

lets try bullseye and r-25!!

 

I don't even want to know what would happen!

 

I did read of someone testing the strength of a Arisaka action.  This guy jammed a bullet in the throat, filled the case with Unique, topped with a bullet and fired it remotely.  He reported that the case was extruded all over the inside parts of the action (which had to be opened with a hammer) but the action was otherwise intact!  (Don't try this at home)!

 



-------------
Regards
303Guy


Posted By: 303Guy
Date Posted: September/07/2007 at 02:55
Originally posted by Dale Clifford Dale Clifford wrote:

...... the same reason I used to dip M-80's in epoxy and get the neighbor kid to light them off......

 

Did the neighbor's kid survive?



-------------
Regards
303Guy


Posted By: Dale Clifford
Date Posted: September/07/2007 at 09:06
Ya, he just wanted more money.


Posted By: 303Guy
Date Posted: September/19/2007 at 03:22

8shots,  I just had to do some more experiments with duplexing!  This time I placed the slow powder over an amount of the fast powder then the rest of the fast powder on top.  That was mainly to blow the partially burnt kernels out the barrel.  Works real well!  I found that the lighter the bullet, the lower the slow powder ratio must be for decent combustion.  I have been able lower the pressure of my hottest load without loss of velocity.  (Using penetration and impact tests for comparison).  I worked up a load that filled the case enough to hold the powder tight to prevent mixing.  I have loaded up some rounds for range testing - prelimanary tests in the field look good.  Of course, this is for fun   - way too much trouble and off the shelf powders available that cannot be beat!



-------------
Regards
303Guy


Posted By: Bigdaddy0381
Date Posted: September/19/2007 at 08:11

  What are you guys useing as a FILLER for when powder dosen't fill the case up???????

whats the pro's and con's of useing it.

 

BIG



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 303Guy
Date Posted: September/19/2007 at 13:58

Bigdaddy0381,

for safety sake, I am not recommending it, but...  I do not use a filler - the slower powder is the filler!  In my case, I find the maximum normal powder charge for that bullet then substitute some of it with the slower powder until I fill the case without raising pressures.  The idea of placing the slow powder over the primer was to gain more burn time and less ejecta velocity but then the powder remains in the bore so I place a little 'normal' powder over the primer first.  That gives me good burning and clean bore.

As to the pros and cons, well there are no real pros except for the fun and the fact that I can use my existing powders to gain max performance with a heavy bullet.  That proves to me that I can now go and spend my money on the right powder - that being Lil'Gun in my case.

The cons are simply a lot of effort!

From a safety aspect, consider that I am doing this in a hornet using a normal hornet powder in conjunction with a slower powder - no small pistol powders involved!  The hornet case is a lot safer to play with than a larger case.  For starters, the base-line pressures are low.  I also tried the three modes of adding the powder to find the worst case.  Slow powder over primer,  slow powder last and mixed.  Mixed gave highest pressures.

 



-------------
Regards
303Guy


Posted By: Bigdaddy0381
Date Posted: September/19/2007 at 14:01

 

 yeah i'm not going to mix powders but i know some people put stuff like corn meal in the case after the powder to FILL the case.i was wounder about something other than more gun powder that can and dose get used as a filler.

 



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 8shots
Date Posted: September/20/2007 at 03:21

Dacron is the standard filler. Toilet paper works just as well, except it looks like its snowing every time you pull the trigger!

303, Thanks for sharing all your duplex experience with us. You really took this all the way!! Maybe Somchem in sunny RSA has a vacancy in their R&D dept for you



Posted By: Bigdaddy0381
Date Posted: September/20/2007 at 09:52

Honestly dose a shell with filler shoot and better than one's with out?

 

 



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 303Guy
Date Posted: September/20/2007 at 13:32

Apparently, the filler works by holding the powder in a consistent position.  I am told that with some powders, this is important.  My uncle was involved in this sort of thing and related a particular cartridge that would not shoot well.  He found that by chambering the round with the rifle pointing up, and then slowly lowering it to the rest, it would shoot well.  This was to do with how the powder lay in the case.  The makers then changed the powder to one that filled the case better.

 

(I have heard of chamber 'ringing', caused by the filler slamming against the still stationary bullet, causing an impression in the chamber neck - I think this has to do with how the filler is used?)



-------------
Regards
303Guy


Posted By: 303Guy
Date Posted: September/20/2007 at 13:47

8shots, two points - firstly, a fellow on another forum has found that using 200gr RP bullets gives him sub-minute groups with his 300 H&H.  Also, they say that 165gr BT's shoot well in all rifles.  Second, how well does your powder fill your case?  It occurred to me that a 1 in 10 twist barrel should not be sensitive to velocity.  It seems that a higher load density is sometimes required to obtain a more consistent burn.

 

(Just out of interest, I do not size my cases at all and contrary to what everyone said, it does not cause pressure problems or inconsistent burn - in fact, I have achieved some rather neat accuracy from a rust damaged barrel, even with lead bullets at full power).

 



-------------
Regards
303Guy


Posted By: Bigdaddy0381
Date Posted: September/20/2007 at 14:07

 so dose a filler drive up the pressure's? dose it ruin barrel life and make a bigger mess during cleaning?

 

Just woundering

thanks

 



-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 8shots
Date Posted: September/21/2007 at 03:17

BigDaddy, Somewhere on the web is a discussion on detonation. Essentially when a case is not full of powder the ignition from the primer sets the whole lot off at once. The result is that the action can blow up. This is an issue that is not fully understood and draws a lot of debate. As 303 says, it is mainly used when small charges are used in order to keep the powder against the primer. This leads to more consistant ignition and thus better grouping of your shots. I do not think it alters anything else, other then preventing detonation as oppsed to burning.

To quote one article:

A safety filler for underloaded firearm cartridges, in which the volume of powder is less than the volumetric capacity of the powder chamber. The filler comprises a sleeve that is inserted into the powder chamber, which radially reduces the typical interior volume of a cartridge shell so that a lesser amount of powder charge fills the remaining space to about 90% of its available capacity. Being preferably made of a flexible and resilient material, the filler sleeve can be inserted into a cartridge shell having a necked-down configuration. The specific configuration of the filler sleeve provides for a reduced volume powder chamber within the cartridge to allow an even distribution of the powder which will burn evenly and uniformly, allowing safe firing of the bullet.
And another:
about low charge detonation in firearms>

>spread out along the bottom of the case with a lot of airspace left above
>it, it can -- sometimes -- detonate or at least burn MUCH more rapidly

In fact, it will burn too slowly at the beginning. Later on, the powder
burns very fast.

>According to ammunition and powder companies, the mechanism is not yet
>fully understood.  Meanwhile, reloaders are advised to use
 
Trust this gives some helpfull info


Posted By: 8shots
Date Posted: September/21/2007 at 03:26

303Guy,

I agree with you that a 1:10 twist should stabilize just about everything. For some reason this is not the case with the 300H&H. I have managed to find the correct load for my 200gr Nosler Part, but it did not come easily. I had to shoot quite a few variations before I found the one that worked.

The 300H&H hold 75gr of S385. I am loading around 68,5 gr, so the case is pretty well loaded.

Several recent articles and tests have largely debunked the notion that the case plays a large role in accuracy. One of our local writers and testers of note have duplicated some of this work and used a whole mix of cases, separated brands, mixed brands, high end brands and so on. The end result was that there was not much in it.

The straightness of seating the bullet and case mouth prep and necking prep etc seems to have a far more profound effect on accuracy.



Posted By: 303Guy
Date Posted: September/21/2007 at 04:28

8shots,

The curious thing here is that you found that new cases did not group at all well.  And this is in what appears to be a tight chamber.  Others have commented that the 300 H&H is a more difficult cartridge to load for accuracy.  I just wonder why that could be?  If it were due to head-spacing then surely the same would be true of the Lee Enfield with it's sometimes very generous chamber.  In fact, I have found no difference between new and neck sized cases in any of the three rifles I have loaded for.  (All three had new barrels).  Someone must have the answer!

 

 Something else I find curious - they say that to get good SD in a hornet using Lil'Gun, it is necessary to use pistol primers and a good crimp.  I have only used the equivalent of MP300 in mine.  ( I don't know the newer 'S' designations but that's 'large pistol powder' - good stuff too).  My powder is AR2205/H4227 and I get it to burn with just an air rifle pellet in front of it.  (That pellet delivers more power than a 22lr!)

 

By the way, it was my uncle who designed the Musgrave model 80 rifle.  He had an un-blued action after his retirement that I never asked him for - rats!  You don't seem to hear much of that action - the rifle was updated a few times - the model 90, I think, was a lighter rifle.  Nice action.  Basically, it was a combination of the best features of existing actions.



-------------
Regards
303Guy


Posted By: 8shots
Date Posted: September/21/2007 at 04:51

This is a curious thing, but I have decided not to try and understand it. I am going to fireform the cases and get on with the shooting bit. As stated earlier, I have driven myself and those around me nuts trying to understand everything in the hopes of having a rifle that puts five shots touching. I am satisfied with the rifle as is and obtaining 1MOA or there abouts is good enough in the hunting field.

I have ordered a Rem700VSF LH in a 308 cal for the five bullet touching stuff!!

 

Interesting on the Musgrave action. Those actions are highly prized today. My friend has just bought an old Musgrave Target rifle, which he is converting to a Varmint style. It is also in a 308 cal. Yesterday he shot a 3 shot group at 100m all touching, and a 200m allmost touching. Good solid rifles, allthough not the prettiest to look at.



Posted By: 303Guy
Date Posted: September/21/2007 at 05:22

8shots,

 

Those old Musgrave RSA actions were good indeed.  Perfect for varminting.

 

I dropped you a line on you other thread.  I had another look at your kudu.  Beautiful.  Who is the good looking fellow holding it up?



-------------
Regards
303Guy


Posted By: 8shots
Date Posted: September/21/2007 at 05:58
My mini me!!!


Posted By: Bigdaddy0381
Date Posted: September/21/2007 at 08:01

Okay,

so if i get this right it is better to add a filler (tolit paper) or something to make the powder stay in place and burn more evenly.rather than have the primer ignite all the powder up the case.

 

 



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P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 8shots
Date Posted: September/21/2007 at 08:21
Correct.


Posted By: Bigdaddy0381
Date Posted: September/21/2007 at 08:24
So will i need to drop down  (rework) the powder or will it affect it much?

-------------
P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 303Guy
Date Posted: September/21/2007 at 16:08

Bigdaddy0381

I have done this a few times and have never reduced the powder to compensate.  These would be reduced loads already in which we are trying to get the powder to burn normally and to avoid those reported detonations.  In my 223, I used a double base powder which did not require a filler and I did try using cotton wool to hold the powder down.  I did not notice any difference.  That was with a case just over half full (done that way to avoid a double charge).  I was trying to replicate hornet performance.  I have heard it said that ground corn cob might compact on firing, forming a plug that could raise pressures or cause 'ringing' in the chamber throat.



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Regards
303Guy


Posted By: Bigdaddy0381
Date Posted: September/24/2007 at 08:00

I'm using H4831sc powder. The cases I’m using are about 90 to 95% full. I can still heard the powder shaking around in the case. I Have not noticed any accuracy problems with it but the powder not being tight just seems strange to me.

 

Thanks for answering all my questions. I’m going to try the TP filler and see how it works out.

 



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P&Z Firearms , Pro gun cleanings and gun repair and wood refinishing.

Ecclesiastes 10:2


Posted By: 8shots
Date Posted: September/25/2007 at 03:57

With a 90% full case you do not need a filler. Mostly cases are never 100% full and you can hear the powder shake about. Even on factory rounds, you will hear the powder shake about. Mostly cases are filled about 80% of their capacity.

It is only when working on reduced loads with less then about 60% capacity that you need some filler I would imagine.



Posted By: 303Guy
Date Posted: September/26/2007 at 00:03
Originally posted by 8shots 8shots wrote:

.....

It is only when working on reduced loads with less then about 60% capacity that you need some filler.....

 

That's my understanding too.

 

Just out of interest - not a recommendation, I tailor my loads to actually set the bullet depth!  (In my hornet only).  It's to do with my loading technique.  Someone is bound to wonder ... ????



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Regards
303Guy



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