I'm having trouble getting the bolt to go into the bcg on my sport. I thought maybe it was new and needed a bit of force but when I got it in and then pulled it out again one the gas rings was bent and sticking out. What could the problem be? Thanks for advice.
Bolt won't go into the bcg on M&P 15 sport
- Thread starter Dedezelic
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MichiganScott
Member
Like you said, one of the gas rings is bent. It was probably that way when it was forced in during manufacture or when you forced it back in. Buy a set or two (because you'll want spares anyway) and replace it.
I'm sure you aren't the first guy to bend one.
I'm sure you aren't the first guy to bend one.
George9
Member
Only thing you can try to see if that issue, and I think it is also.. you can remove the offending gas ring and see if the bolt goes together in the carrier normally.. Meantime get a few sets of new gas rings to have on hand.. but this may help calm you down and make you feel better. George
Maddmax
US Veteran
RULE NUMBER #1 IF it DON'T FIT,DON'T FORCE IT.
Oh yeah I pushed it in rather than twisting it in which worked at the LGS when the guy there put it in with the two rings that weren't bent. Ordered some new ones. Shot just fine with 2 rings btw. Only gonna do that once though since the new rings are here before the weekend.
rojodiablo
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Addendum to rule #1. If it don't fit; back it out, spit on it, and shove it home!!!
Every once in a while, a set of rings will get the gaps lined up. This will allow the rings to drop out more easily from alignment, and since all the tails are exposed, they can be bent. The most common reason for a ring to hang out in the breeze and get bent is the rings are too dry. Put a good drop or 3 of oil on them, and align them well, 1/3 revolution apart from each other, and you should not have any issues.
Rings NEED to be a bit wet when the BCG is assembled. At least this is an inexpensive mistake and an easy fix.
MichiganScott
Member
Stoner built the design to be redundant.
Next thing you know people will find out that they also work just fine with the gap lined up instead of staggered.
George9
Member
Also don't forget the cam pin.. The gun can explode with out it installed. As it will fire without one installed Per manual!! Small part easy to leave out. G
Maddmax
US Veteran
Addendum to rule #1. If it don't fit; back it out, spit on it, and shove it home!!!
Every once in a while, a set of rings will get the gaps lined up. This will allow the rings to drop out more easily from alignment, and since all the tails are exposed, they can be bent. The most common reason for a ring to hang out in the breeze and get bent is the rings are too dry. Put a good drop or 3 of oil on them, and align them well, 1/3 revolution apart from each other, and you should not have any issues.
Rings NEED to be a bit wet when the BCG is assembled. At least this is an inexpensive mistake and an easy fix.
You can buy rings that DON'T line up. Oiling can cause it's own problems.
For real? Explode?
George9
Member
Yes! For real.. Read the manual! George
rojodiablo
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The bolt and rings were designed to be oiled. Why would you not oil them??
The number 1 reason for AR mechanical failures, bar none, is people who run their rifles dry.
First picked up an M4 in 1989, and have dealt with them ever since. I have seen a lot of rifles fail to operate. And nearly every one, whether military or civilian was caused by a lack of lubrication. Firing pins. Bolts, rings. Slides, and stuck FA. Time and again, neglect that was directly tied to a lack of lube.
I saw several beaten dogs of rifles, and they were kept pretty well lubed and ran just fine, despite their service life.
In the manual from the MFG, and in the .gov manual covering the M4, they all show the bolt and rings in specific getting a few drops of lube.
Maddmax
US Veteran
Some people think if a little is good,MORE is better. Take it from there.
rojodiablo
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Yes, I have seen a couple that looked as though they dunked the whole rifle in a 55 gallon drum of oil!!
It is really amazing how many unique jobs a couple drops of oil will perform; washing, lubrication, stiction (What makes the rings stay in place that tiny little bit) and it is truly amazing to see how a little oil on a wear surface between an aluminum upper and a steel Bolt assembly will allow the rifle to be functioned 10's of thousands of times without failure- yet run your car low, and it seems as though you might as well start writing a check for a couple thousand bucks for a new motor, rear end, or transmission.
Go figure!!!
Maddmax
US Veteran
Yes, I have seen a couple that looked as though they dunked the whole rifle in a 55 gallon drum of oil!!
It is really amazing how many unique jobs a couple drops of oil will perform; washing, lubrication, stiction (What makes the rings stay in place that tiny little bit) and it is truly amazing to see how a little oil on a wear surface between an aluminum upper and a steel Bolt assembly will allow the rifle to be functioned 10's of thousands of times without failure- yet run your car low, and it seems as though you might as well start writing a check for a couple thousand bucks for a new motor, rear end, or transmission.
Go figure!!!
GREAT BIG difference between an engine and a weapon. Go figure. I've been running both in all weather extremes for well over 50+ years and have had ZERO problems. That includes Operating High-Way Heavy Equipment.
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The manual says to put a couple of drops on the rings before assembly. When you install pistons into an engine you do not put the rings in dry you oil them. You dont need oil dripping off of them but you do need them lubricated. I havent seen or heard of many cases of bending one ring but with just a little oil and a slight twisting motion the bolt should slide in easily. If it doesnt then take it out and look to see what the issue is. If you are having to force it you are breaking something.
