Gas Block Position

[hg8057]

Is it considered tacky/bad form to have your gas block extend out past the end of your free float rail or have them both even? I'm building a lightweight rifle for my wife and am looking to save weight wherever possible. Her gas block will either be a low profile or micro with no rails or anything else on it. Ideally, I'd like the rail to be even with the block or have the rail (at most) an inch past the block.

[UWone77]

If the gas block is pinned, I don't have much of a problem with it extending past the handguards, Mk12's had exposed gas blocks. After all that's basically what a front sight post is, an exposed pinned gas block.

However, if you're going to just use set screws, then that's a no go in my book.

I generally don't like to leave gas blocks and/or gas tubes exposed, the handguards do a good job protecting them.

[hg8057]

I didn't even consider the protection aspect of the free float handguard. That's why I'm here asking questions. Lotsa people here that know way more than I do. Thanks.

[UWone77]

I didn't even consider the protection aspect of the free float handguard. That's why I'm here asking questions. Lotsa people here that know way more than I do. Thanks.

Hey we all started somewhere. I was lucky enough to have some good friends who walked me through the process and answered all of my questions.

[FortTom]

You'll have different options with different block/barrel/hand guard configurations. I just finished a VERY thin profile barrel upper. The gas block that was recommended for it was about 1/3 longer than average and used 3 set screws on the bottom. There was no "index" point, so a friend and my self found dead center on the barrel, assembled a jig for it, inserted the set screws just tight enough to mark their location on the barrel, removed everything and milled 3 flats for them (the flat bottomed set screws that came with it (3). It gave the block a very stable purchase with 3 screws, everything went together as should and I used the 15 in. MI SSK free float hand guard on the 16" barrel. Plenty of protection and clearance (the gas block was .625) and I don't have any qualms about trusting it completely. If it were exposed in anyway, I'd go a totally different route. As you gain a little more experience, and see the various options you have, you'll be able to make these decisions pretty quickly. It isn't rocket science, if it were, I wouldn't be able to do it...[:D][BD]

FT

[hg8057]

Well I guess for the lightweight build I'm working on now, when I have both barrel and block I can measure where the end of the block will be. Once I know that I can look for a handguard that will just cover it. Thanks again. I appreciate it.

Sent from my KFTHWI using Tapatalk

[GOST]

What length gas system are you using?

[hg8057]

I'm torn between mid and carbine.

Sent from my KFTHWI using Tapatalk

[GOST]

Mid- length is about 11" and carbine is 9". The new free float rail on the market are so light that the length really doesn't affect weight much. For example a BCM KMR 10" weighs 6.3 oz and the 13" 7.7 oz both weights included barrel nut.

[hg8057]

That's absolutely true. But I'm building this one for my wife. She was in a car accident a few years ago. Carrying things can at times cause pain. I'm not gonna ask her to walk cross country with it but she's interested in shooting so I want to save as many ounces as possible.

Sent from my KFTHWI using Tapatalk

[UWone77]

That's absolutely true. But I'm building this one for my wife. She was in a car accident a few years ago. Carrying things can at times cause pain. I'm not gonna ask her to walk cross country with it but she's interested in shooting so I want to save as many ounces as possible.

Sent from my KFTHWI using Tapatalk

You might want to checkout the Building a Rifle for my Wife Thread. I'm also doing one for the wife and going with the LW theme when and where I find it practical for her.

As for the carbine vs mid, I think carbine gas systems have had an unfair bad rap as if the mid's are some magical soft shooting beast compared to the carbine. I have a ton of carbine uppers, nothing wrong with them. In fact a good 14.5 Mid sometimes needs fine tuning before it will be reliably. I guess what I'm saying is, don't over think it.

[GOST]

My last build is a 14.5" middy, can't really tell if it shoots any softer than a carbine. The Centurion 14.7" carbine is a really nice barrel.

[GOST]

Here's an upper you may want to consider. It's a very LW upper.

http://www.bravocompanyusa.com/mobile/Product.aspx?ProductCode=BCM-URG-MID-14ELWF-KMR10

[hg8057]

That BCM upper sure is nice. I can't come anywhere near to affording it though. My build process is the "payday" method. Each payday I put a little aside until I've got enough for the next part. I really do appreciate your help though.

I'm most likely going with this BCM barrel: http://www.bravocompanyusa.com/BCM-16-Mid-Length-Barrel-Stripped-LIGHT-WEIGHT-p/bcm-brl-mid-16lw%20std.htm

I'll talk to the wife about handguard selections and see what she prefers.

Sent from my KFTHWI using Tapatalk

[FortTom]

My last build is a 14.5" middy, can't really tell if it shoots any softer than a carbine. The Centurion 14.7" carbine is a really nice barrel.
GOST,

I personally don't understand the "shoots softer" thing with folks here. It doesn't get much softer than 5.56, maybe a .22LR? or .17 cal, something along those lines.

But, I could see someone with a medical disability, or some physical restraint that could make them want to get recoil, felt and perceived as near as zero as possible. I recently finished the upper with my Voodoo Arms "Ultra Lite" barrel. I installed a MI SSK (key-mod) rail, and the thing is light as heck. I added a couple of oz.'s back in with an Epsilon combination muzzle brake/compensator. Put it on an existing lower, and it shot like a BB gun. I do run H Buffers in all my AR's, and I think that smoothes 'em out a bit, but I've seen goofballs shoot AR's off of their groins to prove a point to the wary, that they are a very easy gun that even 8 year olds can handle with ease.

Am I possibly misinterpreting what you mean when you say "soft shooting". That's the only thing I can think of.

I put the muzzle brake/ compensator on mine basically to help keep muzzle flip down during rapid fire and will put the other on my scoped LMT w/ bipod for coyote use, to keep the bipod from jumping around all over when firing at the yotes.

But, back to the point, what exactly do you mean "softer shooting"? I can't be recoil, is it?

Thanks,[:D]

FT

[GOST]

Yes FT I mean recoil. If you ever mess with a 3 gun setup with an adjustable gas block and a LW carrier that's been tuned you'll we what I'm talking about. It's not a home defense setup but these hardly move, which is nice when trying to minimize your splits. I personally am not into LW builds, I usually use a government profile barrel.

PS you're starting to sound like my 70 year old dad about recoil.[:D] Nobody said that 5.56 has a lot of recoil, but on gaming setups your trying to get every advantage possible. Even though I personally don't compete I have played around with my buddy's 3 gun rifle and I was impressed.

[GOST]

That BCM upper sure is nice. I can't come anywhere near to affording it though. My build process is the "payday" method. Each payday I put a little aside until I've got enough for the next part. I really do appreciate your help though.

I'm most likely going with this BCM barrel: http://www.bravocompanyusa.com/BCM-16-Mid-Length-Barrel-Stripped-LIGHT-WEIGHT-p/bcm-brl-mid-16lw%20std.htm

I'll talk to the wife about handguard selections and see what she prefers.

Sent from my KFTHWI using Tapatalk
I've used that barrel on a build and it's very nice. For the price and quality you may also want to consider this barrel.

http://sionicsweaponsystems.com/store/product.php?id_product=116

[hg8057]

For the price and quality you may also want to consider this barrel.

http://sionicsweaponsystems.com/store/product.php?id_product=116

I certainly will. I've never heard of Sionics, but with your recommendation, I'll absolutely give it some serious thought. The concentration of knowledge and willingness to help here makes this place invaluable.

[UWone77]

I certainly will. I've never heard of Sionics, but with your recommendation, I'll absolutely give it some serious thought. The concentration of knowledge and willingness to help here makes this place invaluable.

I own 2 of those barrels, picked them up when they were an absolute steal at $159. I think these are one of the best barrels available in the sub $200 market. That title used to belong to the Rainier Arms Select Barrels, but they have since gone up in price.

What other components are you planning on purchasing? I know you said you were a paycheck parts buyer... well then again aren't we all?

[hg8057]

ALG Defense QMS trigger w/an adjuster.
The wife likes the Hogue overmolded grip w/o the beavertail
Perhaps a ALG single chamber brake (light and helps w/recoil)
MFT Minimalist Stock (very light)
Upper and lower from PSA
Basic LPK
Troy Alpha handguard
Magpul MBUS sights (not pro)
Edit: PSA Premium BCG

Can't think of what else at the moment. I'm absolutely open to suggested alternatives in the lower cost range.

Edit: I'll have to get advice on buffer and spring weight.

[RiverRat]

I've used that barrel on a build and it's very nice. For the price and quality you may also want to consider this barrel.
http://sionicsweaponsystems.com/store/product.php?id_product=116

If I were in the market for a 16" general-use piece right now, this Sionics barrel would be the one I would choose. Only 22 oz with my preferred gas system, twist rate and finish all in one place. Added bonus: pre-dimpled (a very good thing for a melonite-finished piece) and offered at a very palatable price. I suspect that in a few months, a lot of people will regret not having picked up at least one of these.

[UWone77]

ALG Defense QMS trigger w/an adjuster.
The wife likes the Hogue overmolded grip w/o the beavertail
Perhaps a ALG single chamber brake (light and helps w/recoil)
MFT Minimalist Stock (very light)
Upper and lower from PSA
Basic LPK
Troy Alpha handguard
Magpul MBUS sights (not pro)

Can't think of what else at the moment. I'm absolutely open to suggested alternatives in the lower cost range.

Edit: I'll have to get advice on buffer and spring weight .

Sent from my KFTHWI using Tapatalk

Instead of the Alpha, any considerations for the ALG EMR Rail?

Sounds like you're on the right track so far.

[hg8057]

Instead of the Alpha, any considerations for the ALG EMR Rail?

Sounds like you're on the right track so far.

Thanks a bunch for the kind words. Since your post above I added a PSA Premium BCG. I'm leaving soon to go on duty so I'll have to check on that ALG rail once I get back home.

[hg8057]

Instead of the Alpha, any considerations for the ALG EMR Rail?

We have a winner. That's exactly what I was looking for. Simple, customizable, and light.

[mustangfreek]

Knew i should of grabbed one of those sionics barrel when they were $159, but still a decent deal at $189

OP, rest of your build sounds allright, and of course people like other things , but i have the troy alpha rail (first build) and i find its a frickin cheese grater on the bare hands, good thing this rifle sits on the bench or in prone all the time (18") spr'ish setup

[hg8057]

...i find its a frickin cheese grater on the bare hands...

That's good to know. I'm looking for all input on what people like and don't like and the whys behind it. Thanks.

[UWone77]

If you were still think of a Troy ... this might be a deal for you:

https://troyind.com/products/16-promo-alpha-upper-receiver-blk