Just got done building this:
Noveske lower w G&R lpk, and DD upper receiver w DD chf 16" mid barrel.
Buffer tube (mil-spec) and spring from BCM.
I compared my buffer spring with the spring that came w. an assembled CMMG rifle, and the difference was amazing. Not just visually, but also the noise and feel when racking the charging handle.
What-if any- are the specs to look for, and are there certain springs for certain gas-lengths, and buffer sizes (mil-spec vs. commercial)
Thanks.
There’s only TWO buffer spring sizes. Carbine and Rifle.
Now often… on crappy aftermarket Receiver Extensions (buffer tubes) the inside is rough… not smooth/slick finished. This will make the spring noisy and increase friction a little bit during cycling.
Avoid aftermarket springs. Believe it or not, the designer of the AR knows more about the correct spring than some douche bag selling snake oil. :eek:
That explains - thanks.
Thinking back, the CMMG apparently had a rifle spring (was longer), and the buffer tube must have been really ugly on the inside. Rough and noisy, creaked like an old bed-spring.
Rifles tend to be a little more chattery. We shot Pappabear’s Colt Rifle stock last weekend and it was a little noisy.
Carbine stocks should have a glassy smooth surface on the inside.
Good to know - however in this case, that CMMG had a car buffer-tube, with an H-buffer, and it was not very smooth on the inside.
Weird.
Interesting that this subject happened to come up. I just got another A5 buffer system for one of my SBRs…
So I was going to re-arrange some buffer tubes. The SBR had a COLT RE on it, but my 14.5 middy had an unknown RE on it with scratchy, loud, and rough finish on the inside.
I ended up moving the COLT RE onto the Middy since it was going to remain a carbine buffer, and the Difference was nothing short of DRAMATIC.
The Colt RE made cycling the middy’s action like glass. I could not believe the difference.
The fit and finish of quality parts is impressive compared to some of the junk out there.
Just out of curiosity, how would you compare the Colt RE to an LMT RE?
LMT RE’s are good too.
The only acceptable action springs (IMO) are Colt USGI, and Sprinco CS. Everything else should be avoided. USGI, and Sprinco are the only ones I’ve seen not cause problems.
If you feel compelled to run CS, look up Grant’s posts about Sprinco’s stuff.
No idea who makes LMT springs 2/2 I’ve had have been fine. Also ones I ordered from McMaster Carr work fine.
Never tried an LMT. But I know a guy with several of them. I’ll have to remember to check them out next time we shoot. I’m sure they’re probably fine.
I remember S.A.W. posting about this issue on WeaponEvolution, but it really came clear when I tried the exact same gun and only changed the “tube”.
I don’t own nor have I ever cycled the action of a Colt so I can’t say anything there. But I can say the UBR entry length RE I have is VERY smooth… the smoothest I’ve ever felt. It actually has a shine to its’ interior. The LMT RE I have is nice. It chatters a just a little more than the UBR tube but still feels quite smooth.
Yeah Colt isn’t the only RE that’s made right. My point is what an amazing difference a chatter marked RE makes in the smooth operation of the gun.
Markm- I see you’re in AZ. Why don’t you go call Mike Pannone a douchebag and let us know how that works out for you. After all, he has been heavily involved in Sprinco product development.
These guys are all searching for a niche and an income that keeps them from getting a real world job.
It’s a free market and God bless them if they can come up with something… Crimson Trace Lasers, Spring nonsense… whatever…
With all respect to guys who bravely served, my money isn’t going to sillyness so some cat doesn’t have to do a daily grind like I do. 
(when the ARMY issues a tech bulletin to replace all M4 springs with this or any other aftermarket deal… I’ll buy into it and jump on board and know I’m not being sold a line of crap)
Seriously? Guys who were NCOs in SOCOM units for a decade or more haven’t been through a grind?
You’re right, it is a free market, but if you haven’t tried something before writing it off as aftermarket garbage, that’s your call. If you can’t swing the $15 cost delta, that’s not my call either.
Do you own any midlength ARs? If so, why? Army doesn’t issue them.
Back on track, many things on the AR have changed since it was originally conceived. Why use a Magpul CTR, for example, if it’s not widely issued? Just food for thought.
Sure. I respect that. I’ve just seen too many former mil guys shilling shit to the point that I’m somewhat cynical.
You’re right, it is a free market, but if you haven’t tried something before writing it off as aftermarket garbage, that’s your call. If you can’t swing the $15 cost delta, that’s not my call either.
I don’t need to buy an Oly to know it’s shit. And I don’t replace parts that aren’t broken. 
Do you own any midlength ARs? If so, why? Army doesn’t issue them.
You’re not getting it. I do have a middy… AND it has a USGI SS spring on its buffer. The ARMY issued a bulletin to replace extractor springs and inserts to the Standardized 5 coil and black insert… that’s what I mean. If they say that the carbine now needs to run on a new action spring… I’ll switch.
The ARMY has no profit incentive to create a false need.
Back on track, many things on the AR have changed since it was originally conceived. Why use a Magpul CTR, for example, if it’s not widely issued? Just food for thought.
The CTR is silly too. There’s no need for TWO levers to adjust a friggin sliding stock. 
Let it be clear… I’m not crapping on Pannone. I have no idea what his involvement is with Sprinco or what their product is at all.
My point is only that I don’t buy off on something just because a Former Mil person is involved.
I’ve bought some snake oil and it sucks (AFG comes to mind). I have 3 CTR stocks and wouldn’t buy another. They’re a good stock just more than I need. I plan to buy the MOE next time. I don’t like the QD on the stock and I don’t need the locking lever. I can also buy my next MOE for about half the price. I do like the additional sling attachment options, stock weld and larger but pad on the MOE/CTR.
No one says everything made for an AR works for everyone. If it doesn’t work for you then it doesn’t work for you, it however doesn’t mean that it doesn’t work for me…I happen to use the AFGs, Sprinco springs, VLTOR A5 REs/buffers and other so-called ‘shit’ by others how shoot about 1/10th of what I do on my dozen ARs, YMMV.