Proper buffer set-up for titanium 308 AR BCG?

Saiga Genesis

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Hey fellas,
I've been researching information for what to put in my lightweight 18.6" Stag 10 build, and I had decided on a Brownell's titanium bcg. I'm now trying to figure out what buffer set-up to run, and wondering if reliability will be an issue, and if I would be better off with a standard weight bcg. Durability is also a concern; I have read that titanium, while strong, is softer than steel.

So, correct me if I'm wrong, but, from what I gather, the best solution will be to run a lighter buffer than normal and have an adjustable gas block. Is that right? What strength of spring should I be using? With how light this set-up is, should I be concerned with this set-up being able to return to battery?

With this set-up, will I be sacrificing any real reliability, given all the different loads I could be shooting through it?

When it comes to buffer tube length, does it matter much whether I go for carbine or rifle length (given I choose the proper corresponding buffer and spring), in context of this set-up? Any particular reason why you guys would choose one length over the other? Perhaps parts are more available for carbine-length buffer systems? Maybe not? Stock rattle? I may throw on a Luth AR MBA stock, if that means anything to anybody.

As for the bcg itself, I know it has a diamond-like carbon finish, so I'm assuming that should ease my mind about its durability, correct?

So, what exactly should I buy to make this a sure-fire build? Even recommendations on the gas block are welcome.

Thanks, fellas.

P.s. Mileageman was super helpful in my last thread, where he mentioned his lightweight build. I know he went for a JP silent capture system.
Thread: https://www.canadiangunnutz.com/for...cy-Mixing-barrel-amp-bolt-manufacturers/page5
 
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Madashell, in your first paragraph you talk about a rifle-length set-up, but then talk about how it would be nice for a compact set-up. I'm a bit confused by this; I believe that rifle-length tube extensions are non-adjustable for stock length, at least not in the same way carbine tubes are, so I'm not sure what you mean. Maybe I'm just not picking up what you're laying down, my friend. :)

And for your second paragraph, I'm thinking that choosing one over the other isn't going to make much a difference, as the buffers, whether carbine or rifle length, can weigh the same depending on how light or heavy I want them to be. Like you're saying though, perhaps there are some idiosyncrasies to either type that would make someone choose one over the other, aside from the obvoius difference of compactness.

It looks like Odin Works makes an adjustable buffer system that only comes in a carbine size, but I suppose I could run a spacer with it if I wanted to run a fixed, rifle-length set-up. When it comes to cheek risers on a carbine stock, though, looks like I'll have to be mindful of the charging handle having enough clearance if I'm carrying it around shortened-up. That's no real concern, though.

Sinasta,
I'll definitely be shopping for the proper 308 parts, and I've seen a fair bit online, so I'm sure I'll find the right stuff. I haven't compared AR-15 to AR-10 buffers in terms of length, though. Whether it's a carbine or buffer length, are AR-15 buffers just a bit longer? I guess that's sorta trivial as long as I know what I'm purchasing, weight-/purpose-wise, and the product is labelled "308," "dpms pattern" and all that jazz. Thanks, man.
 
In 308 if you're going to use a rifle length buffer tube you will need a rifle length buffer spring for 308 and you can also use a carbine length buffer or A5 length VLTOR buffer. You can't use a rifle length buffer with this setup because the 308 BCG is too long.

If you use a carbine length buffer you will need a carbine length 308 buffer spring and you will have to use a shorter .308 carbine length buffer. This is the stock setup the Stag 10 comes with. Those buffers only show for 2 internal weights instead of 3.

My favourite setup is the one I'm using right now which is an intermediate length buffer tube, which is longer than carbine but shorter than rifle, with a rifle length buffer spring and a carbine length H4 buffer. I wanted a heavier buffer but I couldn't find one that wouldn't have cost me an outrageous amount of money. With this setup I'm using the JP Enterprises .308 rifle length ground and polished buffer spring. The spring is stiffer than the average .308 rifle length buffer spring and it also has less coils which means it won't bunch up in the intermediate length tube.

In your case, since you're going for lightweight, you're probably better off with a carbine length buffer tube with a carbine length 308 buffer spring and a H2 CAR .308 buffer. I would recommend the buffer from Maple ridge armory for price and availability.
 
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I had a V7 Ti BCG. All I had was an Superlative adjustable gas block with a DPMS 308 carbine buffer and spring. Rifle length gas system. Ran like a sewing machine.
 
Magpul UBR stock (and integral buffer tube) is also M5 lenght.

On a recent build with Brownells titanium BCG and carbine buffer tube I used a JP SCS. Per JP instructions I chose the standard weight SCS. Upon testing with a fixed gas block I found the standard SCS spring was the proper strenght for the setup. This with an 18.5" barrel.

Not sure why JP suggest the light SCS with a light BCG. But in my mind using an H2 buffer behind a light BCG defeats the purpose of weight saving. I'd rather try a stronger spring and adjustable gas block if required.

A different build with a 20" barrel was overgassed and required an adjustable gas block. I'm under the impression that the 18.5"/20" difference makes a big difference in port pressure and bolt timing.

With so many variables and options you can't be sure how it will run. An adjustable gas block may be the easiest and best solution to some issues. I still prefer to give a try with a fixed gas block for the sake of fewer parts. Just accept that you may need a bit of tuning before you can really rely on it.

For testing I use my weakest load and lightest bullet: 7.62 surplus. Once this runs nice and smooth, .308 ammo should run well too.

Recommended adjustable gas blocks are SLR and Superlative bleed-off.
 
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Personally I wouldn't spend the money on the Brownells titanium BCG. I'd rather drop that coin on the JP HP BCG.
Which BCG is this (they have so many options) and why would you recommend it over the Brownell's BCG?

In 308 if you're going to use a rifle length buffer tube you will need a rifle length buffer spring for 308 and you can also use a carbine length buffer or A5 length VLTOR buffer. You can't use a rifle length buffer with this setup because the 308 BCG is too long.
So, here, you're saying that I wouldn't be able to use the VLTOR buffer? I'm not familiar with that anyway, and was leaning to a carbine buffer anyway system anyway, so that's all good. Thanks for the recommended set-up, too. I e-mailed Odin Works and they told me that try out a standard weight buffer and spring as well (while also recommending their adjustable buffer system to tune the rifle, and suggesting I save my money and hold off on buying an adj gas block for now), so I'm sorta leaning in that direction anyway. Honestly, I'm sorta preparing for the worst, and leaving my whole rig in a very configurable state, in case I run into issues or ever switch bolts. I'll probably get the Odin Works buffer, and a standard spring to start, unless JP stuff is just too good to pass up.

Saiga Genesis,

There's an adjustable rifle length version. Think it's called the M5 ? RangerPark explained it above.
Ok, thanks, man. I'll check things out. Been really busy, so I'm sorta late on getting back to you all and researching this stuff.

I had a V7 Ti BCG. All I had was an Superlative adjustable gas block with a DPMS 308 carbine buffer and spring. Rifle length gas system. Ran like a sewing machine.
Excellent to hear. Thanks, Man. I plan on getting one of those now. Which version is best: clamp-on or set-screw?

Magpul UBR stock (and integral buffer tube) is also M5 lenght.

On a recent build with Brownells titanium BCG and carbine buffer tube I used a JP SCS. Per JP instructions I chose the standard weight SCS. Upon testing with a fixed gas block I found the standard SCS spring was the proper strenght for the setup. This with an 18.5" barrel.

Not sure why JP suggest the light SCS with a light BCG. But in my mind using an H2 buffer behind a light BCG defeats the purpose of weight saving. I'd rather try a stronger spring and adjustable gas block if required.

A different build with a 20" barrel was overgassed and required an adjustable gas block. I'm under the impression that the 18.5"/20" difference makes a big difference in port pressure and bolt timing.

With so many variables and options you can't be sure how it will run. An adjustable gas block may be the easiest and best solution to some issues. I still prefer to give a try with a fixed gas block for the sake of fewer parts. Just accept that you may need a bit of tuning before you can really rely on it.

For testing I use my weakest load and lightest bullet: 7.62 surplus. Once this runs nice and smooth, .308 ammo should run well too.

Recommended adjustable gas blocks are SLR and Superlative bleed-off.
Thanks for the help, man! That's very similar to what I'm trying to do here, so it's nice to hear about your results. Expanding on what I wrote earlier, a guy from Odin Works recommended "sticking with a standard weight, because any lost weight in the BCG will have to be compensated for." We see now that both JP and OW recommend that, it seems, so there must be a reason for going that way over heavier springs. Perhaps it has to do with not wanting to have the bcg slamming into battery too hard, or preventing the gun from trying to pick up a round before the follower's ready to bring it up high enough, or that they want to prevent having too strong a spring that would stop the rifle from completing a stroke all the way back.
 
Excellent to hear. Thanks, Man. I plan on getting one of those now. Which version is best: clamp-on or set-screw?

It’s kind of your personal preference. I like the set screws because it’s easy to line up when you dimple the barrel. Also if you have an Mlok rail, usually you can reach the screws. If you use the clamp on, you might run into clearance issues with larger diameter gas block journals.
 
Personally I wouldn't spend the money on the Brownells titanium BCG. I'd rather drop that coin on the JP HP BCG.

This, I went the JP low mass HP BCG route for my stag 10 its hands down the nicest bolt carrier i've ever held in my life as well as being very light.
 
It’s kind of your personal preference. I like the set screws because it’s easy to line up when you dimple the barrel. Also if you have an Mlok rail, usually you can reach the screws. If you use the clamp on, you might run into clearance issues with larger diameter gas block journals.
Does one have to dimple a barrel? I honestly haven't looked into the barrel fitting process very much. As for clearance issues, the barrel has a .750" journal. Is that on the average/large size? Also, how long a handguard do I want to run? Is it necessary to cover the gas block? I think I've seen photos where the block is exposed, and it's just the gas tube that would be protected.

This, I went the JP low mass HP BCG route for my stag 10 its hands down the nicest bolt carrier i've ever held in my life as well as being very light.
Wow, they sound great. On most Canadian sites I'm seeing they go for about $750. That's a bit much for me. Is it cheaper to import from Brownell's? Looks like I could save cash that way, unless shipping and duty fees get me. Any other recommended options? As for low mass steel bcgs like these, I heard they cause more receiver wear because they don't have as much surface area contact with the receiver to spread the weight of the bcg across. Is this a myth?
 
Does one have to dimple a barrel? I honestly haven't looked into the barrel fitting process very much. As for clearance issues, the barrel has a .750" journal. Is that on the average/large size? Also, how long a handguard do I want to run? Is it necessary to cover the gas block? I think I've seen photos where the block is exposed, and it's just the gas tube that would be protected.

You can buy a little jig to dimple the barrel, it’s easy. Some barrels come dimpled. .750” isn’t a large diameter. I usually put a 15” handguard on mine if it has a rifle length gas system. It’s a good idea to cover your gas block, unless it’s pinned on.


You can order a JP low mass from Brownells, it’s under the $500 limit, just have to fill out an end user statement.
 
.750" is the standard journal diameter. If you go with set screws gas block it's good to dimple the barrel first. TNA is cheaper than Brownells on jigs.

To install a barrel you probably want a vice, reaction rod and armorer wrench.

15" and longer handgard are popular lately. To cover the gas block you only need 13.5". To cover only the gas tube and to use a gas block front sight you need a 12.5" (sometimes marketed as 12").
 
You can buy a little jig to dimple the barrel, it’s easy. Some barrels come dimpled. .750” isn’t a large diameter. I usually put a 15” handguard on mine if it has a rifle length gas system. It’s a good idea to cover your gas block, unless it’s pinned on.


You can order a JP low mass from Brownells, it’s under the $500 limit, just have to fill out an end user statement.
Ok, that's all good to know. Thanks!
Honestly, I want the upper receiver to last me a good while, and after hearing how low mass steel BCGs have less bearing surface against the upper receiver, to the point where manufacturers advertise things like "has 100% more bearing surface," I am leaning towards a full-profile titanium BCG instead. During the Canadian boogaloo I'd rather slip in a replacement BCG than install my barrel and mount my optic onto a new upper.

.750" is the standard journal diameter. If you go with set screws gas block it's good to dimple the barrel first. TNA is cheaper than Brownells on jigs.

To install a barrel you probably want a vice, reaction rod and armorer wrench.

15" and longer handgard are popular lately. To cover the gas block you only need 13.5". To cover only the gas tube and to use a gas block front sight you need a 12.5" (sometimes marketed as 12").
Thanks for the tips. I'll probably go around that 13.5" length. Is the superlative gas block easily adjustable under a handguard? Not sure how this works for ease of adjustment.
 
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