No firing pin spring?
- Thread starter N Wolf
- Start date
Steve_in_PA
New member
Free floating firing pin. AR's, M1 Garands, SKS's, etc all have free floating firing pins. You need to understand the design of the firearm.
Yes, firearms with free floating firing pins have the potential for a "slam fire".
The slight dimple on the primer is also perfectly normal.
Yes, firearms with free floating firing pins have the potential for a "slam fire".
The slight dimple on the primer is also perfectly normal.
N Wolf
New member
That sounds risky. So you dring up another question. If I were to reload for this thing what do I have to gain? I have to full length size the brass and I cant set the bullets any closer to the rifleing. How, with that being said, can I make it more accurate. Also, what primers should I avoid to stop the possibility of a runaway.
Originally Posted By: N WolfThat sounds risky. So you dring up another question. If I were to reload for this thing what do I have to gain? I have to full length size the brass and I cant set the bullets any closer to the rifleing. How, with that being said, can I make it more accurate.
o, what primers should I avoid to stop the possibility of a runaway.
Thankfully, slamfires are a relatively rare occurrence in any gas gun, but they have been documented, especially in M1’s & M14’s. It is not unreasonable to also take precautions when loading for an AR just in case IMO.
A slamfire in either the M1 or M14 can have disastrous results if it occurs before the bolt is in battery. The bolt design of the AR would seem to make firing out of battery much less likely since the firing pin is not long enough to reach the primer until bolt locks.
Lack of care in following careful reloading practices or a bit of debris on bolt face, or perhaps a broken firing pin, combined with a soft primer could cause a slamfire, even in an AR.
While the following involved an M1, hopefully it will illustrate what can happen should a rifle slamfire while not in battery. I have personal knowledge of several other such events that I did not actually witness. One was an M14 using military issue ammo in which the shooter received some serious injuries, so the hard primer is not absolute insurance against a slamfire.
A friend who is a very experienced highpower competitor and reloader wrecked his match grade M1 Garand using the same handloads he had used for years when the rifle slam fired out of battery. Bent his op-rod, blew extractor/ejector out of bolt and rounded the receiver locking lug recess about 1/8" showing the bolt lug (thankfully) had barely entered the recess but was not fully in battery at the time the slamfire occurred. He received a cut on the forehead and had somewhat of a problem with his trigger control for a while thereafter. Fortunately, the rifle, and his shooting ability have since been restored.
Upon examination of the remaining lot of ammo, we found that the rounds did not have sufficient headspace (clearance) in his snug, match chamber. He had loaded this batch of ammo using the same (full length) die setting as always. Remember, all previous lots had measured OK. The problem stemmed from the fact that this particular lot of brass had been fired at least 8 times and had work hardened. His dies had been set to give proper headspace with once fired brass and he failed to check headspace on this lot after loading. The harder brass springs back more than softer brass after sizing which resulted in oversized (for his chamber)rounds.
Other than a dirty chamber, a broken firing pin or a pin that is no longer free floating for whatever reason, IMHO, ammo is probably the number one cause of slam fires in the Garand & M14. Anything that can cause the round to "stop short" of fully chambering can result in the firing pin hitting the primer with sufficient force to set it off. If this occurs before the bolt is in battery, it can be disastrous!
Soft primers can contribute to a slam fire. The CCI #34 & #41 military primers have a hard cup to duplicate GI ammo, which is loaded with a hard primer. Handloaders must be aware of two other factors that can result in slam fires.
CCI Military Primers
First, make it a practice to run your thumb over the primer as each round is removed from the press to be sure that the primer is fully seated.
Secondly, each cartridge must be sized sufficiently to fit your rifle's chamber giving proper headspace clearance. I would not load for any "gas gun" without using a cartridge case headspace gauge. Best practice is to run each case through the case gauge at the time the loaded round comes off the press after determining the actual headspace required for your rifle; remember, all rifle chambers are not created equally. At the very least, spot check every few rounds in a given lot of reloads (for this to be acceptable, one must keep all brass in lots that have been fired the same number of times).
Regards,
hm
o, what primers should I avoid to stop the possibility of a runaway.
Thankfully, slamfires are a relatively rare occurrence in any gas gun, but they have been documented, especially in M1’s & M14’s. It is not unreasonable to also take precautions when loading for an AR just in case IMO.
A slamfire in either the M1 or M14 can have disastrous results if it occurs before the bolt is in battery. The bolt design of the AR would seem to make firing out of battery much less likely since the firing pin is not long enough to reach the primer until bolt locks.
Lack of care in following careful reloading practices or a bit of debris on bolt face, or perhaps a broken firing pin, combined with a soft primer could cause a slamfire, even in an AR.
While the following involved an M1, hopefully it will illustrate what can happen should a rifle slamfire while not in battery. I have personal knowledge of several other such events that I did not actually witness. One was an M14 using military issue ammo in which the shooter received some serious injuries, so the hard primer is not absolute insurance against a slamfire.
A friend who is a very experienced highpower competitor and reloader wrecked his match grade M1 Garand using the same handloads he had used for years when the rifle slam fired out of battery. Bent his op-rod, blew extractor/ejector out of bolt and rounded the receiver locking lug recess about 1/8" showing the bolt lug (thankfully) had barely entered the recess but was not fully in battery at the time the slamfire occurred. He received a cut on the forehead and had somewhat of a problem with his trigger control for a while thereafter. Fortunately, the rifle, and his shooting ability have since been restored.
Upon examination of the remaining lot of ammo, we found that the rounds did not have sufficient headspace (clearance) in his snug, match chamber. He had loaded this batch of ammo using the same (full length) die setting as always. Remember, all previous lots had measured OK. The problem stemmed from the fact that this particular lot of brass had been fired at least 8 times and had work hardened. His dies had been set to give proper headspace with once fired brass and he failed to check headspace on this lot after loading. The harder brass springs back more than softer brass after sizing which resulted in oversized (for his chamber)rounds.
Other than a dirty chamber, a broken firing pin or a pin that is no longer free floating for whatever reason, IMHO, ammo is probably the number one cause of slam fires in the Garand & M14. Anything that can cause the round to "stop short" of fully chambering can result in the firing pin hitting the primer with sufficient force to set it off. If this occurs before the bolt is in battery, it can be disastrous!
Soft primers can contribute to a slam fire. The CCI #34 & #41 military primers have a hard cup to duplicate GI ammo, which is loaded with a hard primer. Handloaders must be aware of two other factors that can result in slam fires.
CCI Military Primers
First, make it a practice to run your thumb over the primer as each round is removed from the press to be sure that the primer is fully seated.
Secondly, each cartridge must be sized sufficiently to fit your rifle's chamber giving proper headspace clearance. I would not load for any "gas gun" without using a cartridge case headspace gauge. Best practice is to run each case through the case gauge at the time the loaded round comes off the press after determining the actual headspace required for your rifle; remember, all rifle chambers are not created equally. At the very least, spot check every few rounds in a given lot of reloads (for this to be acceptable, one must keep all brass in lots that have been fired the same number of times).
Regards,
hm
OldTurtle
Moderator - Deceased
N Wolf, I've shot a lot of action competition and only know of one slam fire on a reload and it happened to a friend of mine at a major match...Got him disqualified and I found out that he had used a standard Small Rifle Primer, instead of a Magnum primer (a little thicker/harder)...
If you reload for an AR, try to stay with the magnum level or the military primers and you won't have any worries in that regard..
I would strongly suggest that you work up your loads again when you switch to the magnum primers though...as they do change the reaction of the powder on ignition...
The little dimple you see is a result of the free floating firing pin striking the primer as the bolt closes...Not really something to worry about as long as you practice safe firearm handling by keeping control of the muzzle direction...
If you reload for an AR, try to stay with the magnum level or the military primers and you won't have any worries in that regard..
I would strongly suggest that you work up your loads again when you switch to the magnum primers though...as they do change the reaction of the powder on ignition...
The little dimple you see is a result of the free floating firing pin striking the primer as the bolt closes...Not really something to worry about as long as you practice safe firearm handling by keeping control of the muzzle direction...
Originally Posted By: N WolfWhy would there be no spring? Seems like a simple enough fix. I'll try not to worry so much.
Because there has never been a need for one.
With all of the hundreds of thousands of AR15 rifles, carbines, and pistols out there in the world and seldom, very seldom is there a slam fire issue. If it were a problem it would have been fixed long ago. I have loaded tens of thousands of rounds over the past 35 years and fired a great deal of that ammo through my many AR's and never have I experienced a slam fire. I use standard CCI small rifle primers and Remington 7-1/2 small rifle primers all the time.
Proper case prep is a must with loading for any gas gun and one must follow strict reloading steps to prevent a potential problem. I've had more stuck cases than anything and it's usually due to a bad case.
Now that being said, AR10's do have a firing pin spring but mostly due to the mass of the bolt group and the bolt velocity. They slam home pretty hard.
Because there has never been a need for one.
With all of the hundreds of thousands of AR15 rifles, carbines, and pistols out there in the world and seldom, very seldom is there a slam fire issue. If it were a problem it would have been fixed long ago. I have loaded tens of thousands of rounds over the past 35 years and fired a great deal of that ammo through my many AR's and never have I experienced a slam fire. I use standard CCI small rifle primers and Remington 7-1/2 small rifle primers all the time.
Proper case prep is a must with loading for any gas gun and one must follow strict reloading steps to prevent a potential problem. I've had more stuck cases than anything and it's usually due to a bad case.
Now that being said, AR10's do have a firing pin spring but mostly due to the mass of the bolt group and the bolt velocity. They slam home pretty hard.
Originally Posted By: OldTurtleN Wolf, I've shot a lot of action competition and only know of one slam fire on a reload and it happened to a friend of mine at a major match...Got him disqualified and I found out that he had used a standard Small Rifle Primer, instead of a Magnum primer (a little thicker/harder)...
If you reload for an AR, try to stay with the magnum level or the military primers and you won't have any worries in that regard..
I would strongly suggest that you work up your loads again when you switch to the magnum primers though...as they do change the reaction of the powder on ignition...
The little dimple you see is a result of the free floating firing pin striking the primer as the bolt closes...Not really something to worry about as long as you practice safe firearm handling by keeping control of the muzzle direction...
I'll add one more thing to OT's post and that is If you reload make sure the primer pockets are deep enough and that you seat the primers to the bottom of pocket.. You don't want a high primer.
I bought 500 pcs. of new Winchester 223 Rem. brass and out of the first bag (100) there were three that the pockets were not deep enough. The one time I did not run my finger over the seated primer to feel if it was seated correctly and at the range I did have a slam fire because of a high primer. I was lucky the bolt was at battery so no trouble. Scared the beegeebies out of me. I uniform ALL PRIMER POCKETS for my AR now, don't care what brand of brass I am using. I have always used CCI 450 primers for the AR.
DAB
If you reload for an AR, try to stay with the magnum level or the military primers and you won't have any worries in that regard..
I would strongly suggest that you work up your loads again when you switch to the magnum primers though...as they do change the reaction of the powder on ignition...
The little dimple you see is a result of the free floating firing pin striking the primer as the bolt closes...Not really something to worry about as long as you practice safe firearm handling by keeping control of the muzzle direction...
I'll add one more thing to OT's post and that is If you reload make sure the primer pockets are deep enough and that you seat the primers to the bottom of pocket.. You don't want a high primer.
I bought 500 pcs. of new Winchester 223 Rem. brass and out of the first bag (100) there were three that the pockets were not deep enough. The one time I did not run my finger over the seated primer to feel if it was seated correctly and at the range I did have a slam fire because of a high primer. I was lucky the bolt was at battery so no trouble. Scared the beegeebies out of me. I uniform ALL PRIMER POCKETS for my AR now, don't care what brand of brass I am using. I have always used CCI 450 primers for the AR.
DAB
riverboss
New member
This is good info i had a slamfire a few weeks ago and couldnt figure out whyi put one shell in the barrel and let the action go! booom a big hole in the ground im glad i was point in a safe direction and was paying attention but it still startled me. Im fairly new to ars and couldnt figure it out.
mikeyg
New member
Originally Posted By: riverbossThis is good info i had a slamfire a few weeks ago and couldnt figure out whyi put one shell in the barrel and let the action go! booom a big hole in the ground im glad i was point in a safe direction and was paying attention but it still startled me. Im fairly new to ars and couldnt figure it out. You should never load a single round into the chamber.ARs are designed to feed out of the mag. which adds a bit of resistance to the bolt.Sorry if this has been covered already.
i.hunt
New member
Yep slap the mag in and hit the bolt release and she is loaded best way to load any auto loader from the little .22 to the biggest..... handguns too.... if you must top off mag which I always do I load one right from mag, drop the mag and top off the mag and reinsert it into the firearm make sure it locks in and give it a tug and make sure it is really locked in then off you go...
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Texas solo
New member
Originally Posted By: N Wolf I have to full length size the brass and I cant set the bullets any closer to the rifling. How, with that being said, can I make it more accurate. Also, what primers should I avoid to stop the possibility of a runaway.
Having loaded 1000's of rounds for CMP shooting, I can tell you that you'll need to full length size with SB (small base)die. It's the only way to get 100% reliable feeding.
The greatest advantage to hand loading is consistency. Once you work up a good load for your rifle, every round is the same.
I've always used WSR primers, never had an issue.
Having loaded 1000's of rounds for CMP shooting, I can tell you that you'll need to full length size with SB (small base)die. It's the only way to get 100% reliable feeding.
The greatest advantage to hand loading is consistency. Once you work up a good load for your rifle, every round is the same.
I've always used WSR primers, never had an issue.
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GMM
New member
I have shot a lot of rounds through my 2 ARs and have had only one slamfire. It was a factory load, but I dont remember what brand. The firing pin on an AR15 cant hit the primer untill it is in battery, unless something is wrong with BCG, so if a slamfire happens it normally wont hurt the rifle or shooter, just make sure the rifle is pointed in a safe direction at all times (this should be general safety practice anyways)when shooting and when cycling the bolt.
The slamfire I had was on the first shot while testing accuracy of rounds I had bought. First round hit center of target, second hit about 1/4" higher, so it was in a safe direction, just a bit of a shock to me. Shot 3rd and all other rounds since without a problem.
In my reloads I use CCI 400 primers and have not had a problem at all. Since I started reloading I also have not had a case pull in half either because I run my cases through resizer die then check for dings and correct size. The factory reloads I was buying for a while I had 3 cases pull in half and 2 were a pain to get out.
The slamfire I had was on the first shot while testing accuracy of rounds I had bought. First round hit center of target, second hit about 1/4" higher, so it was in a safe direction, just a bit of a shock to me. Shot 3rd and all other rounds since without a problem.
In my reloads I use CCI 400 primers and have not had a problem at all. Since I started reloading I also have not had a case pull in half either because I run my cases through resizer die then check for dings and correct size. The factory reloads I was buying for a while I had 3 cases pull in half and 2 were a pain to get out.