OpticsTalk by SWFA, Inc. Homepage SWFA     SampleList.com
Forum Home Forum Home > Firearms, Bows, and Ammunition > Reloading & Ballistics
  New Posts New Posts RSS Feed - 308 over pressure?
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Visit the SWFA.com site to check out our current specials.

308 over pressure?

 Post Reply Post Reply
Author
Message
trojan73 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: September/18/2012
Location: flagstaff
Status: Offline
Points: 108
Post Options Post Options   Thanks (0) Thanks(0)   Quote trojan73 Quote  Post ReplyReply Direct Link To This Post Topic: 308 over pressure?
    Posted: April/08/2014 at 23:26
Hi guys
I hand loaded 190 grain nosler BTHP using 41 grains of Varget and using cci rifle primers. The rifle I was using is a Savage model 10 FCP HS Precision. 41 grains of Varget is the starting load for this particular bullet. I believe I am experiencing signs of over pressure based on the flatness of the fired primer, but im not understanding why if im not reaching the maximum load based on hodgdons website. My other observation was one of my fired cases when ejected no longer retained the primer(primer was no longer in the primer pocket). So.....do I load with lower starting loads? If I do, Im not understanding why especially if Hodgdons website states 41 grains is a safe starting load. Any and all feedback would be appreciated, thank you.
To be prepared for War is one of the most effectual means of preserving peace.
George Washington
Back to Top
6\250\40 View Drop Down
Optics Apprentice
Optics Apprentice


Joined: January/17/2014
Location: At the ranch
Status: Offline
Points: 204
Post Options Post Options   Thanks (0) Thanks(0)   Quote 6\250\40 Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 04:58
   Trojan, I consulted 2 other manuals; Sierra and Hornady. BOTH list around 41 gr. as the TOP LOAD. Sierra:  35.4 2200   37.4  2300   39.4 2400   41.4  2500                                                              Hornady:  36.1  2200   38.5  2300  40.9 2400                                                                                     I'll dig up my Hodgdon manual in a bit, but this tells me that 41 gr. is NOT A STARTING LOAD.               Good Luck, let us know how this turns out.
"You'll learn a helluva lot more listenin' than you will talkin'"   My Dad
Back to Top
6\250\40 View Drop Down
Optics Apprentice
Optics Apprentice


Joined: January/17/2014
Location: At the ranch
Status: Offline
Points: 204
Post Options Post Options   Thanks (0) Thanks(0)   Quote 6\250\40 Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 05:41
Trojan, dug out Lyman and Hodgdon manuals. Lyman says  38.5 @ 2322-42.8 @ 2575     Hodgdon says exactly what yours says.  To me, this enforces two things:   Every rifle is a law unto itself, and multiple manuals are a good thing.  Hope this helps.Bandito
"You'll learn a helluva lot more listenin' than you will talkin'"   My Dad
Back to Top
Dale Clifford View Drop Down
Optics Jedi Knight
Optics Jedi Knight


Joined: July/04/2004
Location: United States
Status: Offline
Points: 5087
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dale Clifford Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 08:53

I'd go with the Hodgdon  mainly because I've used this load a lot--- 10k + quantities. I'm betting your using new or fully resized brass which is showing a lot of headspace. Your flatten primers is occurring when the firing pin pushes the entire round forward until it hits the shoulders, then as ignition occurs the primer is pushed out, and as the pressure increases it pushes the case back reseating the primer, but not fast enough. The primer is then flattened. This occurs with low pressure loads, in this case at the 46000 rating by Hodgdon and routinely in straight walled magnum pistol cartridges. After the first fire forming of the cases neck size or only partial with a full length die. The best loads I've found are between 42 and 44 grs. Varget.

I love little league baseball-- it keeps the kids out of the house
Yogi Bera

Back to Top
RifleDude View Drop Down
MODERATOR
MODERATOR
Avatar
EVIL OPPRESSOR

Joined: October/13/2006
Location: Texas
Status: Offline
Points: 16337
Post Options Post Options   Thanks (0) Thanks(0)   Quote RifleDude Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 12:36
Do you have a chronograph? If so, what is your chrono telling you?

More than likely, you don't have an overpressure round. I'm betting you have excessive headspace, as Dale mentions, especially if you're using new, unfired brass. While flattened primers can be an indication of pressure, often as not, flattened primers are an indication of excess headspace, due to the sequence of events Dale describes.
Ted


Money can't buy happiness... but it's much more comfortable to cry in a Porsche than on a bicycle.
Back to Top
trojan73 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: September/18/2012
Location: flagstaff
Status: Offline
Points: 108
Post Options Post Options   Thanks (0) Thanks(0)   Quote trojan73 Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 18:44
Originally posted by RifleDude RifleDude wrote:

Do you have a chronograph? If so, what is your chrono telling you?

More than likely, you don't have an overpressure round. I'm betting you have excessive headspace, as Dale mentions, especially if you're using new, unfired brass. While flattened primers can be an indication of pressure, often as not, flattened primers are an indication of excess headspace, due to the sequence of events Dale describes.
Thanks guys
I do have a chronograph and ill try that out next time I go out. However, to give you a little more info on the subject, the cases im using were fired once before and I was full length sizing. I use rcbs dies pn#15501, should I be using something else?
I do have another scenario to add to the subject. Same batch of ammo but a shooting previous to the one I mentioned earlier. Fired a total of approx 30 rounds. During the course 3 of the fired rounds were difficult to extract. I had to use the palm of my hand to drive the bolt open, felt like the case was stuck in the chamber. About the 30th round the bolt would not open. wacked it a few times with my hand but no give. I finally had to take off my scope, stand me and the rifle up and use my foot on the bolt to force open:( it finally opened. But with half the case stuck in the chamber:( I had to take it to my gun shop would I know does good work and all is well now.
I just dont want to repeat the same scenario as last time.
Where do I start? thx
 
 
 
To be prepared for War is one of the most effectual means of preserving peace.
George Washington
Back to Top
Shenko View Drop Down
Optics Apprentice
Optics Apprentice


Joined: April/20/2008
Location: WA
Status: Offline
Points: 249
Post Options Post Options   Thanks (0) Thanks(0)   Quote Shenko Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 21:41
Sure sounds to me like way too much pressure. No way I'd shoot more of those.
You didn't mention the COAL. Any chance the bullets are seated too long for your chamber?
Did you double-check your scale?
Could you have a different bullet than you think you have? You could weigh & measure some to be sure.
Could you have a different powder than you think you have?
Back to Top
trojan73 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: September/18/2012
Location: flagstaff
Status: Offline
Points: 108
Post Options Post Options   Thanks (0) Thanks(0)   Quote trojan73 Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 22:26
Originally posted by Shenko Shenko wrote:

Sure sounds to me like way too much pressure. No way I'd shoot more of those.
You didn't mention the COAL. Any chance the bullets are seated too long for your chamber?
Did you double-check your scale?
Could you have a different bullet than you think you have? You could weigh & measure some to be sure.
Could you have a different powder than you think you have?
For that particular bullet and my rifle, the seating depth on that round is 2.840 using my calipers but I reload to 2.835.
yes, measure twice load once:)
no, box says nosler 190 BTHP
Ill do that, thx
To be prepared for War is one of the most effectual means of preserving peace.
George Washington
Back to Top
tejas View Drop Down
Optics Journeyman
Optics Journeyman


Joined: March/08/2010
Location: Lone Star State
Status: Offline
Points: 575
Post Options Post Options   Thanks (0) Thanks(0)   Quote tejas Quote  Post ReplyReply Direct Link To This Post Posted: April/09/2014 at 22:50
What kind of brass are you using? Did you trim it? Also, how are you setting your FL sizer up? If your just bringing it down to the shell holder then a hair more, as the instructions say, try this instead:
Bring your die down until it touches then the shell holder, then back it off fall a turn. Chamber the case, if you feel stiff resistance, bring your die down a hair more. Repeat tis until, your case fits in the chamber with just a bit of resistance. Or, make it easy on your self and get a case gauge.

https://www.hornady.com/store/Lock-N-Load-Headspace-Kit-With-Body-1-Each/
Back to Top
trojan73 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: September/18/2012
Location: flagstaff
Status: Offline
Points: 108
Post Options Post Options   Thanks (0) Thanks(0)   Quote trojan73 Quote  Post ReplyReply Direct Link To This Post Posted: April/11/2014 at 11:23
Originally posted by tejas tejas wrote:

What kind of brass are you using? Did you trim it? Also, how are you setting your FL sizer up? If your just bringing it down to the shell holder then a hair more, as the instructions say, try this instead:
Bring your die down until it touches then the shell holder, then back it off fall a turn. Chamber the case, if you feel stiff resistance, bring your die down a hair more. Repeat tis until, your case fits in the chamber with just a bit of resistance. Or, make it easy on your self and get a case gauge.

https://www.hornady.com/store/Lock-N-Load-Headspace-Kit-With-Body-1-Each/
different head stamps, fc, pmc, winchester, hornady, rp, and wra.
Yes, trimmed to 2.010
shellholder plus 1/4 a turn more
Ill try that, thank you
To be prepared for War is one of the most effectual means of preserving peace.
George Washington
Back to Top
Mike McDonald View Drop Down
Optics Journeyman
Optics Journeyman


Joined: September/01/2004
Status: Offline
Points: 739
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike McDonald Quote  Post ReplyReply Direct Link To This Post Posted: May/24/2014 at 21:26

Bear in mind that the loads listed were safe in the testing labs firearm and should only be considered as a guide for use in your guns.


Due to machining tolerances, land and groove dimensions, rifling lead, throat length and a whole laundry list of other stuff, your rifle is different than theirs.

Always use a starting load and work upward from that point.

Also be aware that max load and max velocity might not equate to max accuracy but may equate to max problems Wink


Personally I love 190's in the 308.  Just plain scary accurate at distance.

Best of luck in the search for the grail!

Back to Top
okc4956 View Drop Down
Optics Apprentice
Optics Apprentice
Avatar

Joined: October/13/2009
Location: Oklahoma City
Status: Offline
Points: 135
Post Options Post Options   Thanks (0) Thanks(0)   Quote okc4956 Quote  Post ReplyReply Direct Link To This Post Posted: May/24/2014 at 21:39

Is that a new gun?  You might get your gunsmith to just check your headspace tho he probably did after getting the 1/2 case out.  I got a new Rem 700 a while back that did the same sort of thing (tho not as bad) with loads I was using in a couple of other rifles.  My primers were not flat but the cases were sticking.  Took it to my gunsmith who found a couple of ridges in the chamber that seemed to be catching the case when it was fired.. he polished the chamber and it seems to be working ok now.  Funny thing was that new factory loads didn't stick in the chamber.  I've not figured that one out yet.  I thought it was shoulder thing.  Remington advised me to have my die turned down a couple of thousandths to set the shoulder back a little more.  I still thing the chamber is not exactly right in that gun but sort of set it in the safe last fall and haven't gotten back to it yet.

Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.126 seconds.