Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Slam fire


Recommended Posts

I recently built an aero precision ar 10 in 6.5 creedmoor as a hunting rifle. I now have a slam fire issue. This is caused by the free floating firing pin striking the primer on bolt release. I don't believe this is a problem in a target rifle when you are sending a chambered round down range, however with a hunting rifle you may not fire a chambered round and intend on re-chambering the round for several hunts. My question is, is there a compatible bcg with a firing pin spring for my build? If not, why isn't this an option?

Link to comment
Share on other sites

Yeah....that's not suppose to happen. My 308s always dimple the primer but never ignite the round. I'd pull some bullets and experiment with empty primered cases to get this figured out before I took that gun anywhere. That pin shouldn't have enough ass to fire rounds by itself. I'd look to see if that hammer is releasing when you drop the bolt. What is your build spec? What recoil system? Trigger group?

 

Also, just for clarity sake, you don't have an AR10. AR10 is a specific model made by Armalite. It actually does have a spring on it's firing pin. 

Edited by blue109
Link to comment
Share on other sites

On 2/5/2022 at 7:53 AM, DustBuster said:

Take your hammer out and see if it still happens.  Something messed up with seers maybe 

This. In order to confirm that a slam-fire is the actual issue, you need to eliminate a sear issue as the source of your problem. The other potential issue you may have is a firing pin that's binding in the forward position.

Link to comment
Share on other sites

On 2/5/2022 at 5:14 AM, Uncle Treefrog said:

My rifle is an aero precision ar-10 in 6.5 creedmoor. This is an issue I am having where the gun goes off on closing the bolt. Yes with a bang not just a dent. I was using federal 140 gr ammo.

Does it slam fire when the safety is engaged ? 

Chamber a empty cartridge by hand into the chamber and slam the bolt shut while the safety is on, then put the safety on fire and see if the hammer falls. that will eliminate the safety, sear and trigger if the hammer falls when you pull the trigger. eliminate every cause for the fireing pin punching the primer and causing the slam fire.

Next slam the bolt shut with the safety on FIRE and then pull the trigger to see if the hammer falls.

You could probably do this without a empty cartridge in the chamber, but maybe not.

Edited by mrmackc
Link to comment
Share on other sites

Have you cleaned the BCG lately?   Did the gun work ok for a while and then start this?  Has it done this since the first time you tried to shoot the rifle?  If the safety was in the SAFE position then the firing pin may be stuck.  My DPMS LR-308 has not slam fired while I have had it.  It was lightly used when I got it.  It does NOT have a firing pin return spring in the BCG.  

Link to comment
Share on other sites

On 1/29/2022 at 4:27 PM, Uncle Treefrog said:

I recently built an aero precision ar 10 in 6.5 creedmoor as a hunting rifle. I now have a slam fire issue. This is caused by the free floating firing pin striking the primer on bolt release. I don't believe this is a problem in a target rifle when you are sending a chambered round down range, however with a hunting rifle you may not fire a chambered round and intend on re-chambering the round for several hunts. My question is, is there a compatible bcg with a firing pin spring for my build? If not, why isn't this an option?

Your DPMS style AR 308 does not have a firing pin return spring, nor do most DPMS rifles, and yes they will likely all dimple primers when you release the bolt.. but, it should not result in a slam fire..Who's bolt carrier group are you using??? is it clean and lubed, does the firing pin slide freely in the firing pin channel, back and forth without resistance.. clean it, and lube it, and only load two rounds in your magazine..  try some different ammo... if it still slam fires, pull your fire control group out of your lower, again only load on in the magazine, drop the bolt... I will add that this is NOT a common problem here on 308 AR. So your rifle has all Aero Precision components?? or did you mix and match.. we do like pretty pictures,, maybe show us the firing pin protrusion from the bolt face?? it could be to long?? who knows at this stage, but get back to us, and these gents will help you work through all these questions and get you some answers.

The only manufacturer who does use a firing pin spring is ArmaLite,,, I take that back, Smith and Wesson puts them on their MP10, (more for CYA, but they had an MP10 that did slam fire due to a broken firing pin return spring, jamming in the firing pin in the forward position) its also possible you have a very light trigger?

Edited by billymagg
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...