Originally Posted By: bigedp51Makes me wonder what CatShooter would have to say on the matter.
Remington ran Lake city from 1941 till 1984 and used the Rem 7 1/2 primers in all the 5.56 ammo to light off harder to ignite Winchester ball powders that had more deterrent coatings.
Remington operated LC from inception until 1984, followed by Olin Corp (Win.)until April, 2001, when ATK (owns CCI) took over operation of the plant.
Interesting article(s) by Clint McKee and others of Fulton Armory mentions problems w/M1/M1A's and even links to early problems w/M16 slam fire:
http://www.fulton-armory.com/faqs/AR-FAQs/SlamFire2.htm
http://www.fulton-armory.com/faqs/AR-FAQs/SlamFire.htm
Originally Posted By: bigedp51How did Remington and Winchester get by not having CCI #41 and #34 primers, Meaning the Remington 7 1/2 primer went through the testing phase of M16 development long before the so called CCI milspec primer was ever thought about.
Remington's part in resolving the slam fire issues encountered w/the M16 is discussed in articles linked above as are the firing pin changes to the rifles.
ATK currently runs LCAAP, and since CCI is one of their companies, I would assume they are using CCI primers in current 5.56 and 7.62 ammo production. I have no experience w/either Win. or Rem. primers in gas guns, nor have I ever had a slam fire personally, but do have personal knowledge of one slam fire which occurred with Fed. Match primers and just read another account here:
Quote:Back to M1A/M14 rifles for a minute.
While shooting last time, I let a buddy shoot my S.A. M1A with cheap UMC ammo. While shooting it, there were times when it would slam-fire. This hasn't happend with match ammo, but it still bothers me that it has done it with other ammo.
Can someone give me the low-down on how to cure this problem?
D. West
USA - Wednesday, January 20, 1999 at 09:11:27 (ZULU)
D.West...
My M21 slamfires with Fed F210M match primers... it's caused by the heavy weight of the firing pin hitting on its own speed.
CCI makes a hard military spec primer for this problem... one for the .223, and one for the.308... I think the number for .308 is CCI #34. Check with your dealer.
Pablito
USA - Wednesday, January 20, 1999 at 09:49:42 (ZULU)
http://www.snipercountry.com/HotTips/Slamfire.htm
Since I found no mention regarding use of the 7 1/2 or 9 1/2 primers in gas guns on Remington's web site, I plan to continue to use the CCI's which are specifically made for that service.
Originally Posted By: CCI
CCI® No. 34 and No. 41
MILITARY RIFLE PRIMERS
Military-style semi-auto rifles seldom have firing pin retraction springs. If care is not used in assembling ammunition, a “slam-fire” can occur before the bolt locks. The military arsenals accomplish this using different techniques and components—including different primer sensitivity specifications—from their commercial counterparts. CCI makes rifle primers for commercial sale that matches military sensitivity specs that reduce the chance of a slam-fire when other factors go out of control*. If you’re reloading for a military semi-auto, look to CCI Military primers.
*Effective slam-fire prevention requires more than special primers. Headspace, chamber condition, firing pin shape and protrusion, bolt velocity, cartridge case condition, and other factors can affect slam-fire potential.
http://www.cci-ammunition.com/products/primers/primers.aspx?id=30
Originally Posted By: bigedp51 Second, the only difference in the CCI #41 and #34 primers is the anvil is shorter and thus requiring a harder blow to set it off.
From the CCI website
And the military requires the primer to be seated .008 below the rear of the case.
So all you need are Remington 7 1/2 and 9 1/2 primers that were used by Remington for the M1 Garand, M14 and M16 rifles when they ran Lake City.
Mil Spec primers will not protect against dirty chambers, broken firing pins, oversized cartridges, etc. So,
Originally Posted By: hm1996It is a good idea to run your thumb across the face of the case head as you remove it from the press to check for possibility of a high primer and to run each case through a case headspace gauge to insure proper fit in the chamber of your rifle.
As pointed out by CCI above, other factors that can contribute to a slam fire are:
Originally Posted By: CCIEffective slam-fire prevention requires more than special primers. Headspace, chamber condition, firing pin shape and protrusion, bolt velocity, cartridge case condition, and other factors can affect slam-fire potential.
Regards,
hm