I’ve experienced sluggish bolt carriers with a standard action spring myself.
At a Magpul carbine 2 last fall I ran with a standard action spring, and experienced 5 failures to fire on account of a BCG not being full seated. I was running a 14.5" LMT with a M4-2000.
I normally run a Sprinco extra power spring with a H2 buffer (like I did at Carbine 1 with zero issues) and after that I figured that suppressor use deposits enough carbon, and burns off enough lube that using an extra power action spring is a good idea
Ya it gouges them weither their fed from the left or right side of the mag, I’m thinking it’s the square cut outs in the feed ramps that let the bolt go through & lock that might be doing it. I’ll try to get some pictures here but I’ve been swamped at work lately.
I’m a big fan of the Springco Blue and Red Springs…but my favorite is the Tubbs Flatwire buffer spring. It is a quality spring that behaves more like a rifle spring (stiffer on pre-load than a normal carbine spring and slightly lighter toward the end of the recoil stroke).
I had the same problem with my Noveske 10.5" that you are having. I threw a Wolff Xpower spring in it and went to an H3 buffer and then it ran perfectly. I have had no more issues since this change and now have 2000K rds threw it.
I ended up measuring the carbine lenth spring and it was at minimum length from the factory. Stuff happens! Like I said, it runs EXCEPTIONALY WELL! with and without my HALO on it.
I would never say that a 10.5" gun was QUIET until I started running a Noveske 7.5" upper. Like they say at E.A.G. “Like an Evil Loud Violent Dream!!!” Alsi running an Xpower and H3 in this one. Runs Well.
I have no experience with Wolff springs in carbines (though all my pistols, except my service Glock 21, have been running Wolff springs for years). I know Wolff makes quality springs.
Darkop, I’m curious; how would you compare the Wolff XP spring to a Springco Blue or Red Spring?
Until now, I thought all springs were created equal. What advantage do you gain from an after market spring? Are they made better than a mil spec buffer kit?
Another question, will a spring “shrink” after say 4k rounds? I purchased a new rifle. Switched out the springs to use the old (from a carbine) to put in the new (middy). The new was noticeably longer. What gives on the shrinkage?
I too just had this problem at the range a couple of days ago. I run a 14.7" barrel not suppressed. I shot 60 rounds with three mag changes with no problems seating the first round (shooting pmc bronze .223). I switched over to some leftover Remington UMC .223 I had and on the first mag change it would not seat the first round. I did three more mag changes with the bolt locked to the rear and all three did not seat the first round. Got home and broke the rifle down and it looked like I shot 500 rounds rather than 120, due to a ton of carbon all over the bolt and bcg. After clean and lube and trying to replicate the problem loading and reloading again and again with same mags and ammo, I’m really starting to think it has something to do with the ammo itself.
