M1 firing pin bridge question.

[Slamfire]

Would it interest you to know that the receiver bridge cam you make so much of was really there to retract the firing pin as the bolt opened, not to prevent the firing pin from moving forward on bolt closing?

I am of the opinion that the receiver bridge is there to retract the firing pin as the bolt opened. Davidians emphasis the retraction on bolt closure as a protective measure.

Springfield Armory in an American Rifleman article from the 60’s describes both functions, so pick which “original intent” you want to cheer for.

Just a few simple questions for Slamfire. How many "slamfires" have you actually seen or had happen to you with an M1 rifle?

I have had two out of battery and at two in battery, all with Federal primers. The second out of battery was with federal primers in cases that I had reamed the pockets to depth and primed by hand. Later inspection of loaded cases showed the primers were at least .005 to .008” below case head. The out of battery slamfires occurred while firing from the clip.

Frank had an out of battery in a 308 Garand. Joe L blew the receiver heel off his Garand. He had a newly installed Wilson barrel. He had been given a sizing die, maybe the cases. He did not set up his die with case gages. He used Federal primers. He told me, “people ought to know how dangerous these rifles are to load for”. AJ blew the handguard, split the stock, his rear sight aperture was taken off, the roller came off his bolt, on his out of battery slamfire in a M1a. AJ was using Federal primers, claimed that some of the remaining rounds had cocked primers. AJ told me that he became more particular about reloading after that. I talked with AJ about this on the 15 April.

How much experimenting have you actually done? With what primers? Have you ever deliberately weakened primers by filing?

Two blown up rifles is all the experimenting I ever plan to do.

How many "in battery slamfires" have you seen/had?

I had at least two with Federal primers in Garands. Had one with WSR in the AR15, my Bud who was scoring me, he got up and had one on his relay with Federal Match. I talked to him in Dec, he had another in standing with the AR and Federals, he is not using Federals anymore. A slamfire will cost you ten points, and since he competes in HM class, that is the match.

Have you ruled out wear or tampering with the hammer hooks and sear?

When the M1a ruled the firing, and before decent two stage triggers for AR’s, every so often someone’s rifle would double. The M1a’s would chug, chug, the AR’s had a different noise. We would let these guys fire an alibi string in the rapids, always the rifle would double, and we would then declare the rifle unsafe and have it removed from the line. If you took the rifle off before the alibi relay the shooter would get argumentative, but on the second double, there was no doubt the hammer was following.

Slamfires due to mechanical problems are not subtle and they don’t go away. Slamfires due to primer sensitivity are subtle because they can be 1:9000 events, or 1:64 million events, depending on primer sensitivity.

How? Have you undertaken such a simple test as grinding off the firing pin tang and testing primers for slam fire?

No and I have no desire to see if I can get my M1/M1a’s to slamfire in battery or out of battery.

The M1 was a military rifle, made for use by the military. The military made, or contracted for, the ammunition. They didn't really care what kind of primers someone decided to use sometime in the future, only what was in the ammunition they used in the service.

I totally agree. Soldiers were issued the ammunition they were supposed to shoot. This ammunition was tailored to the operating characteristics of their service weapons.
What I am most upset about was the deliberate omission on the part of those NRA technical writers on the risk of using sensitive primers in these mechanisms. Something that if I had clearly heard, I would never have used Federal primers, and would have not had to replace two receivers. Instead all you heard was “high primers and worn receiver bridges”.

And slamfires did NOT happen.

Absence of reports does not mean that slamfires did not happen in the military. The military did not and does not report to the public an amazing amount of information.

If you did not hear about it, it probably due to the fact that you “do not have a need to know.”

There are things going on, people being injured, people being killed, money being wasted, covert activities that you will never ever hear about.

The military is very good about keeping negative information in house.

How many slamfires have your seen or had with milspec primers?

Only web reports of slamfires with military ammunition.

308 Garand Slamfires with Military Match Ammunition.

http://forums.accuratereloading.com/...66&r=615101566

“In the summer of 1968 or 69 the Atlantic Fleet Rifle Matches were plagued with slamfires using .308 Match ammo. Seems a terrible long time ago, and I still get upset about it because I lost my best and only chance to leg out on that cartridge. I was in the first relay at 500 yards (not 600 because the Annapolis range only went out to 500), and someone else popped off the first slamfire and dumped a bullet into Chesapeake Bay. I think I was the second or third to do so, and dropped my score from winner to first leather. The range officer did not allow a refire for any of us in first relay. By the second relay, the ammo malfunction was quite evident, and refires were given, but nothing was done for those of us in first relay. Slamfires popped all afternoon, was not a pretty sight. On examination, and believe me everyone was looking at ammo that day, the decision was a batch of overly sensitive primers. I guarantee, a slamfire can run your entire day!!!”

From Old Culver’s forum:

I opt for the #34. A number of my friends who shoot the Garand regularly use LR primers. One who specializes in ballistics for a large ammunition mfr says it is imperative to have the primer seated .005", no less but a std LR primer is safe.

The # 34 will not save you from the many mistakes that can be made with a Garand, but will add some insurance against death or severe injuries that can occur even when you have all the safety bases covered.

I started shooting the Garand in 1958 in service, was a unit armorer, have owned and fired Garands for close to 50 years.

One slam fire is enough to coax a person out of complacency. Fortunately, the bolt gouged into the receiver a third way back so my right hand and arm were the only recipients of countless tiny pieces of hot brass. Since I was old enough for the doctors not to worry about blood poisoning over time, they left the brass in the tissue.

The cartridge was a 'Garand safe' commercial match round. Two gunsmiths found nothing to indicate a problem with the rifle, but after checking the primers/seating depth surmised that the firing pin dimpled-fired the LR primer in the round.

That occurred in 1999 and since then I have fired over 8,000 rounds through several Garand's, all using CCI #34 and have not had any problems. I think the major authors/gunsmiths who specialize in the Garand will tell you to use the #34.

If you really get curious about primer seating depth, mic some Lake City milsurp, some commercial Match ammo and some of your own loads, if you load. If you have any of the LC, a quick visual will show you that the primers are seated quite a bit deeper than any commercial ammo. And they are mil-spec primers, less sensitive than std LR commercial primers.

2008 slamfire with Greek HXP 88 30-06 ammunition.
http://www.jouster.com/cgi-bin/reloa...ad=31735#31762

Re: M1 Garand / Hang fire ?
Levisdad <Send E-Mail> -- Tues 3 Jun 2008 8:54 am
Yep 1988, Lot hxp 88j001-002
I also had a slamfire out of this same lot a short time ago.
The slamfire was from closing the bolt using a two round clip. It was the second stage of rapid prone. I've fired 200 rds after that with out a problem. Until the two hangfires.

Slamfire with HXP 20 Feb 2010

http://www.thecmp.org/forums/showthr...?t=8784&page=2

Today, 09:03 AM
chevycrazy69
Join Date: Oct 2009
Posts: 11


________________________________________
I have had one slamfire with a M1 garand. I was single loading during the sighters portion of a NRA high power match. Sure scared the crap out of me. I put the garand down and finished the match with my AR. I was using HXP ball. I have no idea what caused the slam fire. It has made me much more careful in how fast I let the bolt forward during single loading. I have fired hundreds of rounds (both reloads and ball) in that garand since without a single problem. I have used CCI 34 primers in all my garand reloads since. Do I feel it is needed, no. But I am a design engineer and like to take a "belt and suspender" approach to my safety. I do use winchester small rifle primers in my AR and have for many thousands of rounds. I wish I knew if that particular HXP round had a high primer or not.

http://handgunsandammo.proboards.com...ay&thread=9424

M1 Garand woes...
« Thread Started on May 2, 2010, 4:39am »
________________________________________
Well, today I got to attend a super-awesome marksmanship clinic on how to improve our positions for highpower shooting using sling support. I learned *a lot* The big take away was to really practice and stick to the fundamentals and get those things down.

The icing on the cake was to be a course of fire. I was using my treasured M1 Garand rifle and 1980 HXP Greek M2 150gr. ball ammunition. During the slow fire prone I was putting individual cartridges in the chamber, and then closing the bolt. During this exercise, I had an out of battery cartridge detonation. Confused and shocked me a bit, but fortunately the rifle was pointed down range, and the fired cartridge case jumped out backwards, sailed past me and hit me in the arm/torso/leg area. The primer was pimpled out and extruded a bit, but otherwise everything held together. The diagnosis was that the firing pin may have become elongated and may need replacing. I hope it is something simple. I switched to firing an unfamiliar M1 rifle, and encountered the frustration of not really knowing where it hit, and having to make adjustments on the fly. Then I had five cartridges and a magazine jump out of the rifle half-way after the third shot was fired. Then I shot an off-hand string, which was all over the paper, and I realized belatedly that the gas cylinder and the attached sights were loose and free to slide fore and aft!

So it was frustrating, to say the least. I've literally never had any issue or problem with an M1 apart from a cartridge case buckling and causing a stoppage once, and i stopped using that brand of ammo and never had a repeat. But today was clearly not my day.

Thoughts?

Read more: http://handgunsandammo.proboards.com...#ixzz1268Lr7Uw

Garand Slamfires with Greek Ammunition

http://www.thehighroad.org/showthread.php?p=7446022

Yesterday, 07:53 PM #6

ArchAngelCD
Member


Join Date: November 25, 2006
Location: PA, USA
Posts: 9,272 Almost forgot to mention this, I bought 6 cans of Greek M1 ammo from CMP. In the second can I opened I actually had 3 slam-fires from 3 different clips. Didn't happen with ammo in the first can, didn't happen again with the rest of the ammo from that can or the next 2 cans of ammo I used. (192 rounds per can, 768 total rounds) Go figure, never happened to me with my reloads using standard CCI and Winchester primers as well as CCI #34 primers but I got 3 with ammo specifically loaded for the Garand by a government arsenal!

Garand Slamfires with issue ball and NM ammunition

http://forum.1911forum.com/showthread.php?t=251078

11-23-2009, 12:23 PM
lowflash
Member Join Date: Dec 2005
Posts: 233

Quote:
Originally Posted by GRPfan
I've only read about first-hand slam fires (not hearsay) on the Internet a couple of times. There are two problems with this. First, we believe what we read on the Internet, and while a lot of good info is out there, so is a lot of misinformation. Also, we cannot get any kind of statistical information for how often slamfires happen.
Three slam fires with M1 rifles:
1964 ITR Camp Geiger NC International Harvester Mfgr M1 with issue ball ammunition, 1968 Gitmo Marine Marksmanship Instructor for Sailors using M1 rifles converted 7.62 Nato with issued 7.62mm Match XM118 Lot LC 12010, and a M1 Springfield match conditioned by Clint Fowler in 7.62 Nato ammunition .308 Federal Match. All three rifles were examined and found to be with in specification.

Garand Slamfire with CCI #34 primer
http://castboolits.gunloads.com/showthread.php?t=35116
08-25-2008, 06:46 AM #17

B747
Boolit Man



Join Date: Jul 2005
Location: Sioux Falls, SD
Posts: 125 Also, keep in mind that the Garand has a floating firing pin that will at the very least make an indent mark on the primer if you release the bolt from all the way back.

I've had a slam-fire on mine even with a CCI #34 military style primer with the hard shell is supposed to help prevent that. When single round loading I now drop the bolt from about half way closed to keep bolt closing speed down.

A slam fire is always a bad deal --- if it occurs out of breach lock, really bad things will happen.

Wally

Slamfires with commercial primers:

Garand Slamfires with Federal American Eagle ammunition.


http://www.thehighroad.org/showthread.php?t=366406

dmftoy1
Senior Member

Join Date: 11-17-03
Location: Lexington, IL
Posts: 1,947 FWIW if you're going to use commercial ammo (non-nato) I would not single load if you decide to do any service rifle matches as the softer primers (IMHO) are a greater risk of a slam fire. I was recently shooting next to a guy shooting Federal American Eagle 150 grain (30-06) in a Garand and he had a slam fire upon releasing the bolt. I think if you're loading from a magazine you're probably ok as the extra "drag" slows down the bolt slightly.

Just my .02

Regards,
Dave

Garand Slamfire, likely Federal Match Primers.

http://www.thecmp.org/forums/showthr...?t=8784&page=3
22 Feb 2010

Today, 03:52 AM
mopardoctor
Member Join Date: Dec 2009
Location: Fife, Wa
Posts: 64

________________________________________
I was laying next to another shooter on the 300yd line when he had a slam fire on his Garand. He was shooting it as a match rifle and had a globe front site on it. The shock of the bolt slamming back whipped the rifle so hard the front site broke off the base and went flying. I found the case later on the other side of my position and gave it back to the owner. The shoulder and neck were blown out all the way to the end of the case and the end was then rounded to a 30 caliber hole. He said he was using "match primers". Other than the broken front sight there seemed to be no other damage.

Garands Doubling with Federal Ammunition

http://forums.thecmp.org/showthread....light=slamfire

08-07-2011, 07:01 PM
huudoo
CMP Customer Join Date: May 2011
Location: East TN
Posts: 119
Feedback Score: 2 reviews, 100%

WHAT CAUSED a DOUBLE TAP
________________________________________
was shooting today and got a double tap kinda
inspected the casing and found this with the primer
also clip ejected after the 5th round
ammo is BVAC m1 garand, purchased from CTD

i have shot about 200 rds of m2 hxp with no issues
the BVAC mmo case at the rin is smaller than the hxp

would the bolt cause this, or me pulling the trigger to soon
or the ammo ....

and how do you stripp the bolt withOUT the tool

BVAC – Bitterroot Valley http://www.bvac-ammo.com/

CTD- Cheaper than Dirt


http://forums.thecmp.org/showthread....lamfire&page=3

08-08-2011, 11:05 AM
normannewguy
Join Date: Dec 2009
Posts: 105
Feedback Score: 0 reviews

________________________________________
Are you shooting Federal M1 30-06 rounds? If you are I had a thread on them last year and was experincing the same propblem. I finally contacted Fedreal and told them what was going on and they bought back both cases of ammo that I had bought.
Do some testing run HXP, Black Hills Gold, and Hornandy Amax through it. If they function fine with no doubles its the ammo

[Slamfire]

Due to post size limit, I had to split up into multiple posts, my collection of reports of Garand slamfires

Garand Slamfire with Federal Primers

http://www.jouster.com/cgi-bin/reloa...mes;read=31870


Soft Primers Easy Slamfire? http://www.snipershide.com/forum/ubb...Number=1321745

I suppose that this reply will show age on my part, but here goes. I carry a scar on my right palm from 13 stitches due to a slam fire back in the 80's. The rifle was a Match Grade M-1 Garand. Shooting NRA highpower requires 22 shots slow fire from 200 yds in the first stage. Loading a Garand single shot is no monumental task, but here is how it all happened.
While shooting the offhand stage, I was at my 6th shot for record with everything going fine. I slid #6 into the chamber, depressed the follower to allow the bolt to run home, and turned loose of the op rod. The bolt moved forward until it hit the rear of the follower and stopped. This is where i made my mistake. Rather than using my thumb to pop the op rod handle, I opted to bump it with the palm of my hand. Upon closing and partially locking into battery, the firing pin tapped the primer and ignited it. The op rod handle slammed into my palm and opened it up like a sardine can. Wrapped up the hand, went to the saw bones, and 13 stitches later I a fixed man.
That year I personally witnessed 2 other slam fires in matches. All with M-1 garands, and all using Federal 210M primers. One of the other guys has a scar identical to mine, the other person was smarter and got his meat hook out of the way. I notified Federal at the time of my accident to see if they had changed anything in their primer cups. They wanted me to send my rifle back for inspection, but I declined since I was shooting matches with it. Later that year I see an article in American Rifleman about how they had thickened their primer cups due to this problem.
I've never heard of slam fires on M-1A's, M-14's, or Ar's, but feel that it's allways a possibility. After my incident, I learned to allways bump the op rod with my thumb, palm up. That way all meat is out of the way.
You can readily tell if a Garand has ever slam fired. When it happens, it blows the windage knob clear off the sight and removes the top corner of the right locking lug recess in the receiver. I hope I've cleared this up for some. Kevin
_________________________

Slamfire Due to Extra Heavy Recoil Spring
http://www.thefiringline.com/forums/...21#post3977721
Today, 01:21 AM #1

bamaranger
Senior Member

Join Date: October 9, 2009
Location: North Alabama
Posts: 765 garand slam fire?
________________________________________

I am experiencing slam fires in my Garand, after changing the op rod from GI to heavy duty after market. My ammo is properly headspaced, primer pockets uniformed, and uses mil-spec hard skinned primers. I think my ammo is OK. I have reinstalled the GI spring, but have not made it out to shoot again since the slam fire experience. (hey, I always wanted to shoot a BAR!)

My diagnosis is the heavy spring 'caused the prob. I thought I'd made a change to ease wear and tear, but believe I have created a (dangerous) problem. B..B..Bang , PING, what a trip.

Questions:
-Has anybody else experienced a slam fire after an op rod spring change?

-Is there a std for the weight of an op rod spring (lbs pull) The GI spring seems weak, the heavy duty very stiff. What's "right" and how is it determined?

-Tell me what else I should consider, firing pin protrusion, disconnector.....?
I think these parts are OK, as the problem occurred AFTER the spring change, but, can I check them for spec, at home. I do have another trigger group that I can swap out.

Garand Slamfire with Winchester Primers
http://www.mdshooters.com/showthread.php?t=39841

July 12th, 2010, 07:18 PM #16

Drmsparks
Old School Rifleman



Join Date: Jun 2007
Location: PG county
Posts: 4,489
Images: 24
Quote:
Originally Posted by Lambo

I had a Slam-fire occur with my Garand when I was using Winchester Primers. The Cup Metal is to soft in those for use in Military Rifles. I now use the CCI #34 and haven't had that problem since.
Ditto. We have had a rash of slamfires (and blown primers) with the hornady garand match ammo. According to Hornady they were winchester primers.

__________________
RIP


Garand Doubling with Federal Factory Ammunition
http://m14forum.com/ammunition/10706...rand-safe.html

Be careful with Federal M1 ammo. I had two cases of it and experienced nothing but doubles with. Replaced trigger group , firing pin and still doubling. Finally called federal to ask about this and there rep asked how much ammo I had left. I told him and he said box it up and I'll give you a preprinted shipping card and the cost of the ammo back. In all my life Ive never had an ammo company buy anything back. This was 2yrs ago but would still be wary of it.

When I had my problem with Federal I tryed HXP, Black Hills,and GI Lake City Surplus , handloads with CCI #34 primers. All of it functioned fine except the Federal and I kept getting doubles with it Federal. Myabe I got a bad lot I don't know

Garand Slamfire with Federal Primers

http://www.thehighroad.org/showthrea...hlight=federal

Mine was once more than nine years ago and it rattled my faith in the old girl for sure - I mean it's a GARAND!

It was the first round of a full clip and the rifle closed all the way (as far as I could tell) so the only damage was to my trust in things. The round went downrange safely - even hit my target backer although I hadn't set into aiming the shot. It fed the next round just fine which was also Federal primed and didn't fire that one. I unloaded the rifle.

I set that rifle aside for the day as I wasn't sure what had happened. Another shooter asked me about the primer used and told me for the first time I'd heard it that Federal primers were too sensitive to use in semi-auto rifles. I didn't know any better and still am not sure of it but I've never had one slamfire using Winchester or CCI priming. I know that one incident isn't enough to substantiate a blanket condemnation but seeing you say it struck home for me.

There didn't seem to be anything wrong with the rifle and that's been proved out over a couple thousand rounds since, so I've taken it on faith and not used a Federal primer in any of my Garand rifles since.

It's a Springfield Armory, 1-55 date barrel but it isn't original to the receiver, though it came from CMP on another receiver that I converted to 7.62. It measures like a new one and has three "P" stamps, one "T" stamp, the small "m" and "A217B" on it. A couple of people have thought that it was a barrel designated for NM use, but I don't know any of that. It IS a good shooting barrel though.

I only know that nothing about the barrel or the receiver (so far as I can tell)contributed to that slamfire episode. To play it safe I took a little cut to take the headspace out to just short of my "No-Go" gauge because it had felt a little resistant closing on my 'Go' gauge and I thought maybe that could have brought the slamfire. It was probably just my worrying.

I use an old set of RCBS dies, hand prime with a Lee Auto-prime (or whatever it's called) to be sure of my primer set. The round was good but it had Federal No.210 priming and not being able to find another reason for that slamfire I switched to Winchester primers for the rest of my loading for the caliber.
It's been a lot of years since I shot high power matches so now I'm content to shoot CMP ammo, the Greek stuff these days

Garand Slamfires with Federal Primers
01-07-2009, 04:55 PM
SGT D USMC
FNG Join Date: Dec 2008
Location: oregon
Posts: 13

________________________________________
I had a slam fire in a M1. feel free to disreguard this post because few shooters have first hand knowledge, and even fewer have had one. It only happens to others so why worry, except if you are using federal match (very accrate) primers in a gas gun, You are playing russian roulette. My slam fire was in the mid 1980's. It was with a Federal match primer. I got very involved in this and found 17 cases of M1 slam fires with one common factor, ALL WERE WITH FEDERAL MATCH PRIMERS.

Posts: 161
Joined: Mon Jun 01, 2009 6:19 pm
Location: VA


Garand Slamfire fire with Federal primer

http://www.zombiehunters.org/forum/v...1311&p=1065258

Re: M1/M14/M1A "SLAM FIRE" QUESTION?
by wdial » Tue Sep 08, 2009 4:41 am

When I first got my M1 I was just as giddy as can be. I had not yet received my ammo from CMP so I put some of my reloads into a few clips. I then thought about what that would do to the M1 so I took the rounds back out but hand cycling the weapon. About the 3rd round I let go of the slide and it went off on one of my '1/10 grain below max' rounds. The primers were seated properly and the rounds were all perfectly sized. Only thing I can figure is the Federal large rifle primers I was using are soft. I've now used CCI (I know their about the same company), Remington Winchester and a few others and never had a problem. I have not bought the "hard" primers and the controvery over weither or not hard primers are worth it still goes on. I've found that Federals seem to be a bit softer and just don't use them in my free floating rifles. Heck, honestly my of my reloads go into the bolt guns or my handguns.
Girls, God, Guns and Glory
.45/Pie/AK

[James K]

Slamfire, I am still not sure of your point. If you are blaming Federal for using soft primers, that is one thing, and a valid complaint.

But you started off claiming a huge conspiracy of the NRA, CMP, the Ordnance department, and green men from Mars to cover up a serious design defect (presumably you blame John Garand as well) that causes M1 rifles to blow up all over the place. I agree that the Federal ammo/primer issue is important, but that is not a design defect of the rifle.

Your other complaint seems to be that no one told you about not using certain ammo or primers. <.....Noise.....>

Jim

[Kayser]

So, my new M1A scout arrived today. I disassembled it to do some comparative analysis on things. Right away, something stuck out at me:



Clearly the gun has been fired, and I assume that's from factory testing. But that firing pin looks worn down to me. The right side of this shot is where it would contact the bridge. Maybe it's supposed to have a little chamfer on it like that, but I can't find any pictures on the internet to compare against. I've sent an email to Springfield so we'll see what they say.

Is the pin supposed to have that little chamfer in it?

[James K]

That angle cut is OK (in fact it is too shallow) but that galling isn't. It looks to me like the firing pin is entirely too soft and I think could cause a problem in the future. I suggest either returning the bolt to the manufacturer (if the gun was bought new) or replacing the firing pin with a GI M14 firing pin. If you do the latter, make sure it fits properly; if they messed up the firing pin, they might have messed up the bolt dimensions as well.

Jim