458 Socom BCG "sticks"

Moorvogi · Aug 20, 2018

erwos said:
I'm very confused as to the behavior you're describing. Are you having trouble extracting _unfired_ rounds without mortaring, or are your fired rounds not extracting without mortaring?

The first problem is a chamber issue - rough or maybe dimensional. The second problem is a gas system issue - probably a loose gas block.

I'm having a problem fireing unfired rounds, BUT.. only AFTER firing a round. IE.. if i take said live rounds, lock the BCG back, and feed a round it'll extract fine. If i fire that round (or another one) it'll cycle (eject and feed another round). THis is where the problem starts though. Once it feeds a round after a previous one having been fired.. i have to mortar it.

This is behaving VERY much like a 223 wylde chamber that was head-spaced wrong from manufacture and blew up on me back in december... i dont want that w/ a 458 (or anything.. ever.. again)

omegared24 · Aug 20, 2018

Moorvogi said:
I tried four rounds this weekend. The first one fed/fired with no problems just like before. The second round fed (first fed after round fired) and was TIGHT did NOT require a mortar to get out. I put in another round, fired and cycled. This one DID require a mortar to get out. It's getting better but still not great. Perhaps i didn't clean it well enough.

Shall i "soak" it in break cleaner? Thinking of getting a bucket. spraying it down and soaking it in the cleaner for a bit for those parts i can't reach. After .. 20 mintues??? take it out and lube it up w/ some motor oil.

I'd take it to an expert and let them check it out or send it back. That's a big boom to deal with if it isn't corrected.

I had a rifle that was gummed up but didn't require all that much to clean and lube for it to run. It looked like they put molasses in mine. That sounds like a bigger issue, especially if it's new.

Moorvogi · Aug 21, 2018

omegared24 said:
I'd take it to an expert and let them check it out or send it back. That's a big boom to deal with if it isn't corrected.

I had a rifle that was gummed up but didn't require all that much to clean and lube for it to run. It looked like they put molasses in mine. That sounds like a bigger issue, especially if it's new.

I called the place i bought it from. They told me to call the manufacture which makes sense. I got a hold of them and they were VERY responsive. Requested pictures of the BCG then asked about the magazine. I told them i do NOT have a dedicated 458 socom magazine but was using a USGI ar15 magazine. They are sending me a dedicated one as they feel that's the problem. (puzzled look on face).

i completely striped the bolt (well, more than i normally do anyway). De-greased the entire thing.. and made it bone dry. Then i lubed it up as well as doing the same for the upper receiver and chamber. While i haven't fired it even from a block, it does cycle smoother by hand.

To clarify; i'm not going to shoot it until it's headspace is looked at. That being said; i have the following thoughts/concerns (no particular order).

1. I'm using an H2 buffer (a little heavier than the normal buffer because that's what was in stock when i was buying parts.

2. potential headspace issue. i've already had a .223 wylde bull barrel receiver blow up.. not looking to repeat that.. ever..

3. non dedicated 458 socom magazine?? can someone explain how this would affect it?? I'll even take troll answers at this point (please mark them as troll answers though so people dont get all crazy dumb/defensive etc etc).

erwos · Aug 21, 2018

Lubing the chamber is not a good idea, and can lead to over-pressure issues.

I agree that the magazine seems an unlikely explanation, and could be easily ruled out if you could eject the live round more easily without the magazine in the gun. Buffer also seems highly unlikely.

Chamber dimension issue is almost certainly the problem, and I agree with Chad that it sounds like it's short. It is _possible_ that it is an ammunition dimension issue, but I am super doubtful about that if it's factory ammo from SBR or the like.

jrumann59 · Aug 21, 2018

Is it a coated BCG? With the proliferation of various coatings it could be your lugs are "too" big to unlock reliably. I had a NiB that had the same problem.

omegared24 · Aug 21, 2018

Moorvogi said:
I called the place i bought it from. They told me to call the manufacture which makes sense. I got a hold of them and they were VERY responsive. Requested pictures of the BCG then asked about the magazine. I told them i do NOT have a dedicated 458 socom magazine but was using a USGI ar15 magazine. They are sending me a dedicated one as they feel that's the problem. (puzzled look on face).

i completely striped the bolt (well, more than i normally do anyway). De-greased the entire thing.. and made it bone dry. Then i lubed it up as well as doing the same for the upper receiver and chamber. While i haven't fired it even from a block, it does cycle smoother by hand.

To clarify; i'm not going to shoot it until it's headspace is looked at. That being said; i have the following thoughts/concerns (no particular order).

1. I'm using an H2 buffer (a little heavier than the normal buffer because that's what was in stock when i was buying parts.

2. potential headspace issue. i've already had a .223 wylde bull barrel receiver blow up.. not looking to repeat that.. ever..

3. non dedicated 458 socom magazine?? can someone explain how this would affect it?? I'll even take troll answers at this point (please mark them as troll answers though so people dont get all crazy dumb/defensive etc etc).

That's a good idea to get it checked. Clandestine knows his stuff.

My issue was an obvious mess left by the previous owner. That thing should run no problem after all you've done.

Magnumite · Aug 21, 2018

Have you examined the rounds fed from the mag and mortared out of the rifle? Burnished on the bullet/neck and opposite side of the case. If they are not feeding in the proper manner the round is hitting the feel ramp and not allowed to slide up the ramp into the chamber without abnormal force. This could deform the round enough to cause it to stick in the chamber. I see where a mag with improperly shaped feedlips could cause this.

Moorvogi · Aug 22, 2018

erwos said:
Lubing the chamber is not a good idea, and can lead to over-pressure issues.

I agree that the magazine seems an unlikely explanation, and could be easily ruled out if you could eject the live round more easily without the magazine in the gun. Buffer also seems highly unlikely.

Chamber dimension issue is almost certainly the problem, and I agree with Chad that it sounds like it's short. It is _possible_ that it is an ammunition dimension issue, but I am super doubtful about that if it's factory ammo from SBR or the like.

when i say lube, i ment the regular "rem oil" from cleaning it. not oil/greese etc etc. just like cleaning it then pushing rags thru till clean.

Moorvogi · Aug 22, 2018

I haven't been able to find a gun smith that has 458 socom headspace gauges. I'm tempted to buy a set and donate them to a gunsmith. Before i do that, does anyone reading these posts have a gague i can borrow for.. 3-4 minutes at the AGC range or something?

Give you some $ for the trouble etc etc. Still cheeper than buying them for "single use" reasons.

3paul10 · Aug 22, 2018

I dont have the gages, but I would highly recommend sending that back to Rock River and let them fix it, it would have to be covered (I hope) and even if it didnt pass the gage, what will you do then?? My 2 cents.

Moorvogi · Aug 22, 2018

3paul10 said:
I dont have the gages, but I would highly recommend sending that back to Rock River and let them fix it, it would have to be covered (I hope) and even if it didnt pass the gage, what will you do then?? My 2 cents.

Ahhh the voice of reason. This is why i like these forums and the people in them.

The ONLY reason.. i don't want to send it back is: i wont have a pipe bomb (i mean firearm) in my possession. Which... is not a good reason i know.

Moorvogi · Aug 22, 2018

i consulted the manufacture again and while they are very responsive they are not yet ready to do a return as they want me to try a dedicated magazine first. i have a lead slead, some string... i'll remove the optics and stuff.. point it in a safe direction and see how things go from a safe distance.

i'm not going to hold n fire it for a while.. i'll probably get better than 16 MOA anyway. (humor from another thread).

jrumann59 · Aug 22, 2018

At you using a 458 SOCOM mag or a 556 mag modified for .458 SOCOM?

Moorvogi · Aug 24, 2018

mtlcafan79 said:
Who's ammo? Some are known to cause issues in RRA barrels. A lot of people recommend polishing the RRA chambers too. They're known to be rough.

This is UNDERWOOD 300gr spirepoint.

Moorvogi · Aug 24, 2018

jrumann59 said:
At you using a 458 SOCOM mag or a 556 mag modified for .458 SOCOM?

this is a 556 mag that has had no alterations to it. the manufacture asked the same question. they are sending a magazine designed for 458 and said to contact them if the problem continues. i'm goign to take the sites off... put it on a rest and pull the string from behind a blast wall a few times...

Moorvogi · Aug 24, 2018

it may also be worth noting that this is currently using an H2 buffer, instead of a milspec weight buffer. It's heavier so slower, but perhaps the added mass translates to more smack being laid down at feeding time. can the BCG cycle further back under normal fire than w/ using the charging handle??

jrumann59 · Aug 24, 2018

Moorvogi said:
this is a 556 mag that has had no alterations to it. the manufacture asked the same question. they are sending a magazine designed for 458 and said to contact them if the problem continues. i'm goign to take the sites off... put it on a rest and pull the string from behind a blast wall a few times...

That could be the problem, you have to do some minor alterations to a 5.56 mag to get it feed 458 reliably below shows some slight changes to the lips and follower and a ridge in a magpul

http://bigborear.com/forums/article...odifications-for-50-beowulf-and-458-socom-r7/

Moorvogi · Aug 24, 2018

jrumann59 said:
That could be the problem, you have to do some minor alterations to a 5.56 mag to get it feed 458 reliably below shows some slight changes to the lips and follower and a ridge in a magpul

http://bigborear.com/forums/article...odifications-for-50-beowulf-and-458-socom-r7/

thanks. i'll have to look at link later, it's blocked for me here (at work). I couldn't think of the realistic impact a magazine would have in feeding a round. Let me rephrase that.. i couldn't think of how a magazine could fix a firearm having problems allowing the second round to eject smoothly only after firing the first. I mean.. this issue doesn't exist w/ snapcaps or even the live rounds until i fire them. then the issue is with the next round it feeds.

If it was a magazine issue.. i would think it's the same be it from being fired or using the charging handle. perhaps i'm wrong. Manufacture is sending a dedicated magazine to validate this anyway. should be here today.. we'll see!

clandestine · Aug 24, 2018

I dont have the .458 gauges, but they are available from PTG for $127.00 plus $15.00 Shipping.

If you can't find anyone to look over your gun, I can do it for the price of the gauges.

I normally turn down calibers like this because they can be so problematic, but it appears you are not getting much help from theanufacturer and that pisses me off.

If you decline, I understand. Just wanted to offer my help if I could.

RetiredArmyGuy · Aug 26, 2018

I have a set of gauges and a case gauge but I won’t be able to get to them until the first week of September. You are more than welcome to them. I am going to bet that it will headspace fine. If you don’t roll your own for this caliber you will find since there isn’t a SAAMI spec for the caliber some manufacturers ammunition will or will not load. The bigger issue is that PTG reverse engineered the reamer without authorization from Tepo Jetsu and there are now two different specs for the same caliber. RRA uses the original spec reamer from Tepo Jetsu so you should try using Southern Balistics Research (SBR) ammunition in the RRA rifle because they are the only ammunition manufacturer that is currently authorized by Tepo Jetsu to manufacture ammunition and barrels. Tromix is the only other company authorized and using the actual reamer specs from Tepo Jetsu. All the other companies including Wilson are using a reverse engineered reamer with different specs. I will bet dollars to donuts Underwood isn’t bumping the shoulders back enough to fit the original spec RRA chamber.

If you want to use my gauges let me know and I will get them just shoot me a PM.

458 Socom BCG "sticks"

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