AR10 malfuction help

[Greyfox]

I agree with the prior posts about using a small base dye. I would try this before you change too many variables on your rifle. Tight fitting brass can give the impression that the rifle needs to be constantly lubed to function properly. What could be happening is that the combination of fouling and heat is causing the case to be too tight requiring more force to chamber/eject the round as more rounds are fired. By lubing the action you are compensating for this but not solving the real issue. I had the same problem with mine, and small base dyes solved the problem. I'm not sure that this is your problem, but it's the first place I would go based on your symptoms. When troubleshooting an AR, assuming nothing is broken, it's wise to start with the basic variables first:
Ammo
Clip
Extractor/ejector
Gas system clear
Springs

 

[load]

Thank you, I will try this. know any place that sells replacements?

brownells

 

[scottyd2506]

I agree with the prior posts about using a small base dye. I would try this before you change too many variables on your rifle. Tight fitting brass can give the impression that the rifle needs to be constantly lubed to function properly. What could be happening is that the combination of fouling and heat is causing the case to be too tight requiring more force to chamber/eject the round as more rounds are fired. By lubing the action you are compensating for this but not solving the real issue. I had the same problem with mine, and small base dyes solved the problem. I'm not sure that this is your problem, but it's the first place I would go based on your symptoms. When troubleshooting an AR, assuming nothing is broken, it's wise to start with the basic variables first:
Ammo
Clip
Extractor/ejector
Gas system clear
Springs

I am not having live ammo feeding problems. Small base dies are not going to help with brass extraction, as no matter how small You under size brass it will expand to the chamber!.
I am no expert though, so it could be, have a set of RCBS AR small base dies on order.
Along with 125 Nosler BT's.

Anyone know how the action gas system does with 125 gr bullets vs 168's, or light bullets more powder vs heavy bullets less powder?

thanks for the help. Again

 

[Greyfox]

I am not having live ammo feeding problems. Small base dies are not going to help with brass extraction, as no matter how small You under size brass it will expand to the chamber!.
I am no expert though, so it could be, have a set of RCBS AR small base dies on order.
Along with 125 Nosler BT's.

Anyone know how the action gas system does with 125 gr bullets vs 168's, or light bullets more powder vs heavy bullets less powder?

thanks for the help. Again

You can try hand feeding one of your loaded rounds into the chamber. Push it in with your finger to see if it easily chambers fully and easily. It should drop out with a tap on the butt. This is with a clean chamber. if the cartridge is jammed in too tight you can have cycling issues. At least this is what I have seen. Similiar effect as you see with a bolt rifle showing difficult bolt lift when using improperly sized brass. With an AR this effect will cause a cycling problem.
Gas impingement AR's operate on a particular pressure ramp, usually set up for military type bullet weights and powders. This was a large part of the issue with the early M16's during the Viet Nam war. The early cartridges(powder) were mismatched to the original loads designed for the gas system. Timing is important with an AR. I haven't tried 125's in my rifle, but if the pressure ramp is radically different from the standard buffer/spring set-up it will throw the timing off, which may cause cycling issues. I would be interested to hear as well if others have tried 125's.



problems.

 

[Rhino55]

Scotty
I just built a AR-10 clone (Mega Arms MATEN) I had the same problem and after I chased it for a half day, I checked my gas block aliment and found it off. Look around your gas block and see if you see any "Soot" coming from around it. With my gas guns, Ipour some shooter choice down the gas tube to clean it out. There has been on a couple rifles I've had to open up the hole on the barrel for it to cycle properly. I'm not at all an expert on gas guns but I've found most of my cycle problems dealing with the gas system or recoil spring. An AR-10 has a heavier spring than a AR-15. (found this out the hard way too)
Rhino55 gun)