Ok all you AR10 experts

Ok let me start by saying I can build a dang nice bolt gun but AR's are not my thing, looking for little advice.

I have a project sig 716 patrol that I got for fun. I have rebarreled to a longer barrel 22-243. The rifle shoots lights out but having issues getting it to cycle correctly unless I run the loads really slow which defeats the point. Is there a heaver buffer spring that I can get, or can I turn it from piston to gas block, or is there even a more fine tuned gas block for the piston system that I could get so I can get this thing cycling with the hotter loads.

I'm with you Derrick, ARs are another animal I don't have lots of experience with. The last six months I have had students and buddies at my range, their ARs quit working when I am around

I hear ya, They are "simple" in some ways but trying to tweak them and change parts and know who's parts fit who's is a quandary. Run a 308 or 223 no prob but lets wildcat these things and run some BC and speed

I'm not sure what kind of malfunctions you're having. But if it runs fine at slower velocities, you're system is probably over-gassed. This is actually very common. Especially when you screw a suppressor on the end of an AR-10 type rifle. I would suggest installing an adjustable gas block. Use the load it shoots best with and turn the gas down as you shoot to get just enough to make it cycle like it does with your slower rounds, or to a degree you're happy with.

Derrick,

You will want to get an adjustable gas block to tune the amount of gas coming back to the bolt. For example, if you run an AR-10 in 308 Win at modest speeds, you have a 30 caliber barrel with about 45 grains of powder that bleeds off pressure rather quickly. When the bullet passes over the gas port, you have all the pressure space (volume area) of a 30 cal barrel behind the gas port. When you take a 22-243, you have about the same amount powder, but in a 22 caliber barrel with a much smaller area or barrel volume. When the .224" bullet passes over the gas port, you will have much higher pressures at the gas port since you have a 22 caliber barrel with the same amount of powder but a much smaller volume, which dramatically increases your port pressure. To handle the pressure, you have to reduce the gas coming back to the bolt carrier. I have seen some guys run a 6mm (243 Win or 6mmCM) or fast 22 round in a gas gun. It's hard to hot rod an AR-10. You won't get the speeds near you can in a bolt gun. You will generally lose about 100 to 150 fps, depending on a few factors. Hope this helps!

Chad

An adjustable gas block should help if they make those for pistons. Way too much gas pushing the piston and cycling the bolt. Sounds like it's cycling so fast it's not letting the bullet move up in time.

You don't usually change the buffer spring, you usually change the buffer to a different weight. I THINK you need a lighter buffer for slower cycling. I think it's the lighter weight = less inertia, which leads to a shorter bolt cycle. I think that's right. (Not a pro)

How heavy is your buffer?

I'm guessing you're at about 4-5oz right now -- going up to 6-7oz would probably alleviate the issue. A high power buffer/action spring (Wolff) allong with it will also help

I recommend a JP captive spring set. Smoooth

Adj GB and this......www.sprinco.com

25762 Tactical Springs LLC .308 M4 CARBINE Extension Tube EXTRA POWER Moly-Plated Chrome Silicon Buffer Spring in Hard Tube (Color Coded ORANGE) [NOTE: Developed EXCLUSIVELY for .308 CARBINE Platforms Utilizing Standard 7" Depth M4 Carbine Extension Tubes with Short Buffers. E.G. DPMS/Bushmaster, Etc.]

My sig716 has an adjustable gas block. Does yours not?

This is truth!!! My 6.8 never jammed or failed to feed until JG got behind it...

Sounds like me and copiers/fax machines.

adjustable gas block will do it, just did the same thing with my AR-10, you can use a heavier buffer but that's just fixing a symptom and not the problem...

Thanks guys! I have currently just the factory buffer spring, not sure how heavy it is. The block is adjustable. but not really much its got on off, and suppressor. Can I convert this piston system to a gas system???

Put the buffer itself on a scale and let me know the weight. That's easy enough to adjust

I would try it on suppressor. If you're over gassed and a suppressor causes it to be over gassed, it may fix it. I'm no expert but it knda makes since.

does it run right without the can on?

I don't have a suppressor. I was thinking that since you're over gassed and a suppressor can cause a gun to be over gassed, that the suppressor setting would fix your problem. That's if the suppressor setting constricts the hole some. This is more a guess then anything.

Go ahead and give us a call at Sprinco/ Tactical Springs
1-800-397-9530 toll free.
We will get you squared away and your gun shooting reliably.

No, did not run well with can on it before I changed barrels and calibers ether

Don't own can and its not threaded for one, seems like that would cause more issues as it hold more pressure back, seems to work better with less gas or faster powders

Derek, The "suppressor" setting on you GB will restrict the amount of gas used to cycle the bolt. That should help.

Alternatively, how heavy is your buffer?

I understand that but it does not help, its all factory at the moment

Messaged you back, Derrick