Hello, bought my first AR-10 the other week while the BLEM lowers were on sale. As usual for PSA BLEMS, I can’t find the BLEM. To go with the lower I purchased a basic 16" PSA upper, because I’d prefer to pick out the upgraded parts myself. In this case it may have been wiser to go with an upgraded upper because it looks like I’ll end up with many of the same parts, but this rtoute did get me a nitrided black barrel which I prefer over stainless for my use.
Anyhow I have a few questions about this rifle and components for it.
It appears on the page that the lower uses a standard carbine buffer tube and spring, with a special short buffer. On my ARs I prefer and usually run a Vltor A5 buffer system, both because I like how it runs and because I like the available extra length of pull depending on shooting style. I see that PSA now offers their own version of this buffer sytem, Sabre S5 Buffer.
If one wanted to run the A5 or S5 buffer tube on an AR-10 is it possible, and what components would be needed?
Trigger is usually the first thing I replace in an AR, this one is no different. The stock EPT trigger is surprisingly good. It isn’t my first PSA EPT trigger and they’ve all been good, especially with JP springs and a pretravel set screw, but this seems to be the best without those additions. It’s still getting replaced though. I purchased a Timney Impact AR trigger and it was shipped before I noticed the that it does not work “with AR-10, 15-22, or 7.62x39 rifles”.
Why? Most AR-10s claim compatibility with AR-15 trigger groups. It fits and is installed now, but might be another week or two before I get range time. Can swap triggers between other rifles if it doesn’t work, have both PSA and Velocity drop-in triggers I can try.
Do these use standard DPMS style AR-10 bolt carriers? It isn’t high on my list of things to do, but may want to play around with different ones in the future.
With the carbine tube you must run the shorter buffer or else it will bottom out. I use Geissele triggers in all my ARs, including my ar10. It does use a standard dpms 308 bcg.
I get that with the standard carbine tube, I’ve got to use the short PA-10 buffer. If I stick with the stock buffer tube, I have no reason to change the buffer. I probably want to install a longer Vltor A5 (or Sabre S-5) buffer tube. I’m asking what spring and buffer I’d need to run that tube, if it is an option at all.
I don’t have Geissele in anything, not a good option for me. That said I respect that it is what you like and are willing to pay for it. I’ve been happy with the assortment of triggers I’ve used. If this Timney is anything like the Timneys I’ve tried in bolt guns I’ll be happy with it too. Just a question of if it will work with the AR-10, and why they claim it won’t I suspect it’s simple CYA tactics.
If you use the longer buffer tube like an A5 then you can use a standard length AR15 buffer of an appropriate weight. I’m using an Odin Works AR15 size adjustable weight buffer with the A5 length tube.
The A5 buffer tube length with the longer AR15 buffer weight lets you use a standard length carbine buffer spring. I went with a Sprinco Orange .308 spring in mine. I never tried a Tubbs spring before, looking at the product info it looks like a quality product so I’m sure it would be gtg.
Finally got to the range today (well yesterday) and it ran great. Forgot the good ammo, but the almost 50 year old (1966) Lake City Match 7.62 that dad lying around ran great. Pretty good groups too considering that I’m not familiar with the gun yet.
Performance wise, so far it just has the upgraded trigger. I swapped the FSB for a low profile gas block, and now have an adjustable waiting to go on. Also installed a 3-9x50 Vortex Crossfire optic.
Next outing I’ll have the gas block swapped out, and have the good ammo to properly site in the rifle.
Still want to change to a free float handguard and swap to the intermediate length buffer tube with an H3 buffer. Given that I will be running the AGB, I’ll probably go with a Sprinco RED spring, and tune from there. If I need to step up to the ORANGE, I see* a 450 bushmaster build in my future that can use the red spring.
*See as in I’ve had the upper and a spare stripped lower for a few years, and I’ve almost got enough spare parts lying around to throw together a dedicated lower for it. #8 here we come.
This is going to sound kind of sad, but I think I’ve only taken the rifle back to the range once since that last post, and I don’t recall if it was before or after the buffer change. Shortly after changing it I got cought up in the brace rule stuff and modifying the resultant SBRed pistols, just never got back around to it. I wanted the AR-10 mostly to have an AR-10, I don’t have much cause to waste 308 ammo when the smaller calibers are so much cheaper.
To answer your question… I installed a KAK 9 position A5 length tube. An Odin Works AR-15 adjustable buffer and bought extra tungsten weights, but don’t recall if I installed them. I opted for the Tubbs AR-10 Flatwire spring.
It all fits and cycles fine by hand, but can’t say for certain about in operation. Might have to find the original parts and return it to stock so I can compare the changes the next time I take it to the range.
