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Lapua bullets and Vihtavuori powder

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Blackbird View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Blackbird Quote  Post ReplyReply Direct Link To This Post Posted: November/18/2007 at 12:08

spreader,

 

I use only Lapua brass these days, and you are correct, its the most consistant out there. But, the flash holes are punched not drilled, at least in the 6BR Norma, & .243Win. cases. Now, I know that Norma drills the flash holes in their brass. I haven't used any of todays Norma brass, I have heard that it is too soft, and it is more expensive than Lapua, so ain't no reason for me to change.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 03:12
Originally posted by Mike McDonald Mike McDonald wrote:

, the 100-series or the 500-series?

The 100 series swings less than the 500 series.  The 500 series is a double based blend of nitrogliceryn and nitrocellulose while the 100 series is a single based powder.  Both have a steep knee in the curve below 50 degrees F.

 

, Hodgdon is essentially a blend of powders

All cannister powders are a blend of powders to arrive at a specific burn rate.

When reloading, note lot numbers in your load book.  When changing lots always work back to your velocity or charge weight.

Found that VV, Hodgden, Alliant all have inconsistancies from lot to lot.  Had 4 lots of Re-15 that were exact to charge weight -vs- velocity then 2 lots that were not.

It's just something to account for in the process, and easily done.

 

. Too much prep work needed before I can do anything.

Now is where it really does become personal preference and individual technique.

One of the worlds top shooters switched from Lapua to Winchester as he found no signifigant gain in accuracy over standard Winchester brass.

If you are shooting benchrest, you'll only have 20 or so match cases to load, all carefully prepared and numbered.

If you're going to shoot anything else you may well find that case prep is a very fun thing, and relaxing, but past proper sizing to your rifles chamber and trimming to a uniform langth, all those things we all want to do yield almost no real world  gain for the effort.  New reloaders all want to be really anal about brass prep, we all did it, and then you find that the very simple things result in best performance.

For example, I have gone from owning and using every brass and bullet prep tool on earth to doing the following for loads I compete with;

Weigh brass and segregate into lots ( bought in lots of 1000 and separated)

After you go through 2-3000 rounds you have 4 usefull lots of brass.

F/L resize when new.

Trim to uniform length

Uniform primer pockets

Sierra bullets for comp get uniformed and weighed.  This gains just enough consistancy to be noticed past 600 yards.  I still use non-prepped bullets for practice, the gain is so slight.

All powder charges are weighed after a charge weight is deternined.

New powder lots are tested when purchased.

Purchase primers in bulk.  Buy 8,000 primers for your new barrel, all same lot.

That ends that hassle.  New barrel, new primers.

I use scale check weights.

 

.....use different primers for loads for your bolt guns vs. your M1A?

 

No, I use Federal 210 primers  ( not match) in all loads except ball powder, then I use WLR primers.  This has proven to be a consistant recipe for sucessfull load development that I've adhered to for 20 years.

 

The overall sumary is that I try to uncomplicate a process that can become overly complex just because we want it to.  Results show that less can really be more.



Mike,

Just realized that 64 pounds of powder, with average weight per load being 45 grains comes to nearly 10,000 rounds. That's quite a lot of shooting, and quite likely more than one barrel. Someone has a lot of free time on their hands

As far as VV powder goes - thanks, this is helpful information. That's actually very surprising, since usually double-base powder is supposed to be more stable in different environmental conditions.

I guess I will stick to Hodgdon for the time being. Any recommendations for use with 308 Win in Sako TRG-22? Varget or H4895?

By the way, somewhat unrelated question. I'm curious, what barrel twist would be sufficient to stabilize 185grain bullet in 308 Win?

When I mentioned that Hodgdon is blended powder, what I really meant is that they don't manufacture the powder itself. If I'm not mistaken, gun powder today is manufactured by only three companies in US - DuPont, Alliant as part of ATK and Olin Corporation. I might be wrong about Olin, but DuPont I'm certain about, unless ATK already bought their gunpowder making business too. If someone has more up-to-date information I would be glad to hear it.

Vihtavuori actually manufactures their powder, therefore giving them more control than what Hodgdon can have.

I thought about weighing all new brass, but then realized - if I later fully resize it and need to trim, it may very well turn out that 1 grain weight difference between the brand new cases disappears with removed material. And trying to make the process easier is what I'm after as well, that's why I personally prefer Lapua brass, because it seems that cases are far more consistent, therefore making my life easier.  May potentially move towards Lapua bullets as well, for anything beyond 500 meters. Time and practice will tell.

And I agree, no reason to sweat too much for making practice ammo up to say 500 meters. It's only what gets used beyond that, that has to  be done very very carefully. I don't compete in benchrest, don't find it personally interesting. Of all the current long-range civilian competitions F-Class probably appeals the most to me. It's somewhat irregular though, I guess in few years if it becomes much more popular it would be of more interest, since local competitions will hopefully happen more often. But even without competitions, shooting long-range was always most interesting to me - very challenging and thus very rewarding.

However, being very far from "nearest" 1000-yard range also makes a good argument for painstakingly making more than just 20 rounds to use at that distance. After all, traveling over 200 miles to such range with the goal of practicing at that distance with only 20 rounds makes little sense. So, naturally, I need to load more than 20 rounds at once, that's why I need simple, repeatable and consistent process.

In fact, I don't even try to do it all at once in the same day. One day I would prep the cases, another day select bullets, yet another day prime the cases. The only time I do two things in one day is powder charge and seat the bullet.

Then check the assembled cartridges, which now would include using the Bersin tool I recently bought.

I can seat the bullets and then make slight adjustments, making sure every cartridge has a bullet dead-center, once again improving consistency. Still getting used to it, and though it's one more tool to have (and mess up with), it should be helpful. Reloading for 1000-yard use is probably never about saving time and money Although calculated over 10+ year period it would probably save quite a lot.

I'm actually also at the stage where I'm trying to decide whether I should use traditional press (I have Forster Co-Ax) and dies or arbor press (like Haydon's) with L.E. Wilson dies. Arbor press with L.E. Wilson dies makes it all very easy and simple. At the same time, full-length resizing is easier with traditional press. I guess I will be keeping both for a while.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 03:16
Originally posted by Blackbird Blackbird wrote:

spreader,

 

I use only Lapua brass these days, and you are correct, its the most consistant out there. But, the flash holes are punched not drilled, at least in the 6BR Norma, & .243Win. cases. Now, I know that Norma drills the flash holes in their brass. I haven't used any of todays Norma brass, I have heard that it is too soft, and it is more expensive than Lapua, so ain't no reason for me to change.



Interesting. If Lapua punches the primer holes, these have to be the cleanest punched holes I have seen in cartridge brass. So, it's way better than Winchester and Remington anyway. I have bought 1000 cases of Lapua in 308 Win, after trying small batches from Winchester, Remington and Lapua. I haven't seen a single Lapua case with burrs in primer hole. And they're very consistent in terms of size and weight. And annealed necks are a big plus.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 03:28
Originally posted by Dale Clifford Dale Clifford wrote:

what gun you shootin the good stuff in spreader? most store boughts can't see the difference.


From now on it would be Sako TRG-22. Really like it. More so than any US-made "factory" rifle currently made in fact.

And you're probably right - most store-bought rifles would see no difference, but since most store-bought rifles probably can't shoot accurately beyond 500 meters, reloading for those rifles makes sense only if you practice a lot and already have a reloading gear.

Also, I bought some Black Hills match ammo once - out of 200 rounds I had to put aside about 20-25 rounds which I probably should return to Black Hills - they have necks that are almost collapsed. That's NEW ammo.

When I'm the "manufacturer", the "quality control manager" and the "consumer" - I have a better chance of producing something I could really use
And I actually find the process quite relaxing. Maybe it's just me
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 11:03

JBM has a good "twist rate" calculator.  check out their site.

shoot long range couple of times a week, 500 to 2 miles, usually load 100 300 win. mag, 200  308, 100 6.5-284, usually 200  223 sometimes less (usually work in 400-600 IPSC practice rds, and some skeet on weekends for relaxation if no match) . my grandma can shoot 500 yds. who shoots it the fastest wins  (her arthritis acts up occasionally and hurts her times)

 disagree that practice loads require less attention than match rounds or loads for ranges less than 500 yds, if your practicing, especially for a match, and don't place importance on each and every shot, the only thing you've learned or practice is that the gun goes bam when you pull the trigger-- can't use the excuse you missed because of non-quality ammo. Dillons work great.

only real advantage I've found to Lap brass is "stiffer" primer pockets allowing more hot loads per reloading.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 14:17
Dale,

As far as practice loads go - what I meant is less attention given makes practical sense, since slight variation in the load won't affect accuracy as much at short distance. So, if the bullets happen to be not exactly 175 grain, but 175.2 or 174.8, or powder charge is 0.1 grain over or under normal weight, or overall cartridge length is plus/minus extra quarter millimeter - it's acceptable. Obviously if you're preparing for competition it makes no sense to do so, but during regular practice I see no problem with "slightly irregular" loads. To put this into perspective, most balance scales have error of up to a full grain, calipers bought for under $200 have errors of up to 0.1mm  and micrometers in that price range would often err up to  0,01mm and yet huge number of people are using those regularly.

Speaking of calipers, I have tried several different types of caliper attachments to measure overall length of cartridge and was disappointed. I think most that are sold for reloading public aren't good, very inconsistent, measuring same cartridge using my Etalon I would often arrive at results varying quite a bit. What do you use for this purpose?

As far as barrel twist calculators go, the problem is that I have no dimensions for the bullet in question. I have seen quite a few calculators around (that normally include as little information as possible about methods they use to come up with results), but they all require bullet dimensions. So, if anyone regularly shoots the 190gr Sierra in 308 Win or 185grain Lapua Scenar, it would be helpful to know which barrel twists you got to stabilize it.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 15:55

 sorry only etalons I come accross are used in wavelength measurement, (if so thats "overkill"). when even necessary just a digital to 3 decimal places. (usually mag length has more to do with it). In my mind the statiscally random errors introduce by only throwing charges, (after weighing) and the off set in some other part of the reloading cycle will cancel. This means that everyone will shoot a 2 in. 1000 yrd group. given their fortitude at the task and enough time. The theortical advantages of minimizing error related (or introduced error) is off set by noncontrollable factors, (temp, wind) and min. these usually give better results than extreme attention to detail at the reloading table. The ability of a handloader to "batch" his loads of course is its advantage, but the fact remains, (just as cleaning a gun) no one method works better than the other. Mike's method and getting an es that low is all that matters -- for him. anyone else trying to dup. the process would be a failure. the amazing thing is that so many reloaders using different techniques over such a large time frame, using components that have been standarized, (canister powders) get such consistent results at all. Obviously no single method is best or everyone would be using it, and just like trap shooting or skeet shooting everyone would be wearing the same eye blinders as the current winner.

1x11 will stabalize up to 210 vlds- I believe trg 22 are 1x12 in 308 and my 42 is 1x11 in 300.

( I shot a 146x150 in skeet yesterday so don't mess with me--I'm superman.)

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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 16:35
Dale,

Etalon is the top of the line micrometers, dial indicators, indicating micrometers, calipers and other gages made by Tesa in Switzerland. There is no better quality product made today anywhere else in the world.
You won't find them in typical tool store, but specialty dealers that sell equipment to best machinist shops usually have those. The best supplier of those in US today is probably Long Island Indicator.

Any digital caliper with "3rd decimal place accuracy" without proper mechanical design is just a marketing gimmick. Try it on high grade Mitutoyo standard gage blocks (either metal or ceramic) and see how consistent a typical one would be (you will be unpleasantly surprised). In the long-term vernier calipers are also more reliable and accurate than any dial-style calipers, be it fully mechanical or mechatronic. There is also one other thing about mechatronic calipers - once that circuit fries, it can't be fixed, you can only throw them away and buy a new pair.

Seems like I will be trying 185grain bullets then. TRG's use non-standard twist rates - slightly faster than what is common on other rifles.

TRG-22 has a 1:280mm twist rate (1:11.0236") in 308 Win (as well as 300 Win Magnum on TRG-42)
TRG-42 has a 1:305mm twist rate (1:12.0079") in 338 Lapua

As far as skeet goes - nice shooting. Shotguns are not my thing though



Edited by spreader
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 16:46
it is a mitutoyo digital - gimmick or not- worked great so far- I think I'll keep it.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 17:37
Depends on the model of course, but overall Mitutoyo is not bad actually. Their metric dial calipers that are Made in Japan are pretty good for the price, around $100. They won't last you 30 years though. The Brazilian ones that are imperial aren't a good investment.

In that price category I would buy a Tesa actually. This one for example is very accurate and reliable and not as expensive as Etalon:

http://longislandindicator.com/p97.html
(either model is great)

It would last you probably at least a decade with normal use (and quite possibly a lifetime with repairs every decade or two), without loss of accuracy.

If I had to create a rating scale based on accuracy, quality and longevity, I would say that Etalon was best for calipers, micrometers, indicators of all kinds, Tesa was number two for calipers and micrometers, then Mercer/Compac for dial indicators not made by Etalon, followed by Mitutoyo for calipers and micrometers, followed by Brown & Sharpe for mechanical calipers and micrometers made in Switzerland (their mechatronic ones and the ones that are made in USA are worthless junk) and last place would be Starrett.

And then the Worthless Pile of Junk category - everything made in China, Malaysia, Indonesia or other 3rd World country of your choice, regardless of brand name. In that sense Redding/RCBS/Hornady/Franklin and all these other reloading-equipment companies that are slapping their names on these and advertise them as necessary tools for "precision" reloading make me very suspicious of the quality of their other products. I'm sure you would never see a BMW slapping their name on Yugo-made "car".



Edited by spreader
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 18:13
got the long one for oal on .50 cal. somewhere around $200
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike McDonald Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 18:31

By the way, somewhat unrelated question. I'm curious, what barrel twist would be sufficient to stabilize 185grain bullet in 308 Win?

 

Depends on how fast/far you expect them to perform.

A 1:12 will take care of the 190 if you keep it above 2600fps, which precludes use of Varget, it's too fast.  H4350 or Re15 are the standards there.

 

185's like to fall out of the sky at about 800 yards.  You can drive them fast but thus far they seem to be a middle distance performer.  Lapua loads them to 2485 fps for a reason.


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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 20:52
Mike,

I obviously want them to perform to 1000 yards (or better yet 1000 meters).

185's are falling out of the sky at 800 yards out of what rifle? (which twist rate?) [TRG-22 has 1:280mm twist rate]

Not sure which Lapua load you're referring to though. I only see these cartridges listed on their website:
http://www.lapua.com/information/products/caliber/sport-shoo ting-cartridges-ccf-rifle/308-win-7-62x51/imperial/zoom/
http://www.lapua.com/information/products/group/special-purp ose-cartridges-rifle/imperial/zoom/

And according to that data the loads with 185gr remain supersonic at 1000 yards.

For reloading, Vihtavuori data for 185grain Scenar out of 610mm (24.0157") barrel:

N550 40.5gr@2203fps
N550 46.9@2608fps

For 185 FMJBT (D46) out of 610mm (24.0157") barrel it shows:
N140 37.6gr@2215fps
N140 43.7gr@2551fps

So, out of 660mm barrel it should be about 50fps faster. I'm actually not sure how significant MV would be to stabilization of bullet in this case. I'd think twist rate alone plays a much more important role.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike McDonald Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 21:11

I've shot the factory D46 from several.well two actually, 26 inch barrels, one  a 12 twist, the other an 11.25:1 twist.

 

Velocity on both is 2485 and inside 500 meters that load is scary accurate.

Tried driving them faster and things don't work as planned.  Sometimes theoretical ballistics and actual results part company.  You and Dale can work it out amongst yourselves

 

From experience, twist rate vs velocity makes a difference in long stabilization.  While rotation slows on a lesser curve than velocity, it's enough to tell the difference between say a 1:9 barrel and a 1:8 barrel.  The slower twist rate will require a higher velocity to remain stable at distance.  Specifcly the 9 twist barrel will require another 150fps to have projectile stability at 1000-1400 yards.

 

The N550 load you cited works very well with 175 Sierra matchkings at 1000 yards.

It is a case full of powder in a Lapua case though.  (nothing wrong with compression).

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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 21:37
"scary accurate"  - wabbits bewawe 

What do you mean by trying to drive them faster? (if that's a factory load, then how would that be possible?)

My understanding is that rotational velocity doesn't drop even one percent by the time the bullet drops to the ground. So, if it starts to tumble in the air, it's not due to significant reduction of rotational speed, it's due to force of the air drag overcoming stabilizing force of rotation (I may need to rephrase it, trying to think of a better way to explain it). The reason why higher MV appears to have an effect on long-range stability is likely  because when bullet starts to tumble, it has flown farther down the range, thus appearing to be more stable.

So, if it's not stable enough to begin with, it would start tumbling within approximately same period of time that passes since the moment it exits the muzzle, irrespective of muzzle velocity (assuming of course it exits at speed exceeding that of speed of sound and starts to tumble before it drops to below the speed of sound).

Dale seems to believe 1:11" twist should be enough to stabilize bullets up to 210grain in weight with VLD profiles. I seem to recall reading some place that Sako opted for 1:280mm twist rate specifically so that it can stabilize heavier bullets. The important detail that escapes my memory though is what they meant by "heavier" bullets. I can't remember if they were talking about 175 grain or 185 grain...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 22:13

regardless of the spin or twist rate the projectile must still go say one foot to complete the revolution, the elapsed time however changes. bullets do not act as buzz saws, regardless of the rev./sec. a rifle bullet will barely make one complete revolution on its way completely throught an elk, ( one of the reasons hard cast bullets work so well).

as the bullet decreases in its forward travel, (velocity) its rotational momentum stays the same, the further from launch the longer it takes to complete the 1 foot, but the rotational momentum increases in relation to the initial launch conditions.

decreasing heavier bullet velocity in marginal twist barrels will increase accuracy, especially seen in heavier bullets in 22-250' etc.

within the "usable" range of the load speed of sound isn't a factor. obviously aerodynamic turbulance will effect transitions, but the point is to use it before that. Mikes comment about dropping out of the air, is a reference to the fact that the trajectories are not parabolic, but log functions, where at some point the derivative of the drop is increasing, ( becomes 2nd order) and the veritcal component vs. horizontal component of the co-ordinates is increasing for each decimation of the horizontal. (rise gaining over run). If this were not the case , transit time would be to target (or lack of it--time of flight) would be the only material factor. The 204 and 220 swift would rule.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote spreader Quote  Post ReplyReply Direct Link To This Post Posted: November/19/2007 at 23:29
Dale,

"decreasing heavier bullet velocity in marginal twist barrels will increase accuracy, especially seen in heavier bullets in 22-250' etc."

I agree.

This however has everything to do with air drag. At higher velocities resistance on the bullet (the air drag) is more significant than at lower velocities. Since it is acting on the bullet tip from underneath, properly stabilized bullet would turn in direction of twist. But unstable bullet would simply tumble. So, this holds completely true when you're launching a bullet from barrel with same twist at different MVs - slower MV would have an effect of keeping unstable bullet in normal flight for longer time and distance simply because the net force acting on the bullet won't be sufficient to tumble it.

But I was commenting on Mike's observation that said "The slower twist rate will require a higher velocity to remain stable at distance.  Specifcly the 9 twist barrel will require another 150fps to have projectile stability at 1000-1400 yards."

In other words, what he is saying is that if you had bullet launched from barrel with 1:8" twist and it appears stable, same bullet would not be stable in 1:9" unless you add extra 150fps at the muzzle.

That's why I said that if the bullet isn't stable enough to begin with, increasing MV often has an appearance of making it more stable, but in reality it simply tumbles further down the range than it would otherwise. In terms of time however, it seems to me it would happen within the same timeframe as bullet launched at lower speed from 1:8" barrel. I could be wrong of course, I don't have all the answers

So, Dale, from your experience, would 1:11" twist stabilize 185 or 190gr bullet in 308 Win?

Thanks!


Edited by spreader
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike McDonald Quote  Post ReplyReply Direct Link To This Post Posted: November/20/2007 at 06:01
You guys ever think about actually going out and shooting?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/20/2007 at 11:18

about 50,000 rds. a year counting aks, 22 lr, and shotgun. slowed down alot though, used to be closer to 100,000 during match years. wore out 2 hispanic farm worker reloaders.

 

 In other words, what he is saying is that if you had bullet launched from barrel with 1:8" twist and it appears stable, same bullet would not be stable in 1:9" unless you add extra 150fps at the muzzle.

 

not sure if this can be made a cateris parebus arguement.

 

yes  1 1;11 will shoot 190 -I do it in my trg 42 frequently, as well as 210 bergers.

 

This however has everything to do with air drag. At higher velocities resistance on the bullet (the air drag) is more significant than at lower velocities. Since it is acting on the bullet tip from underneath, properly stabilized bullet would turn in direction of twist.

 

I know some long range shooters who cant their scopes to account for this.

 

I read mikes statement to mean , that an increase in muzzle velocity was necessary to make for the decrease in bc and not necessarily related to twist rate--- I'll go through it again.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: November/20/2007 at 11:36

here some good stuff from a group between the stool shooters and the can't stand still action crowd.

 

How do Atmospheric conditions effect a bullet?
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat &Number=37523#Post37523

 barrels - Makes, Models, Opinions
http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat &Number=229850&page=2#Post229850

 

155 palma, 175 smk etc.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat &Number=373195#Post373195

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