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View Full Version : Picatinny Rail on Barrel Clamp? AR accessory help needed.


dcbiii
10-13-2009, 3:27 PM
Hey guys,

Picked up a nice upper and it came with a stainless bull barrel and varmint style grip up front--makes for a nice, accurate rifle, but it's pretty heavy.

I'd love to attach a front grip but all I've got to work with is a bipod stud and a Picatinny rail up top for a front sight post.
http://img62.imageshack.us/img62/2091/dpms.jpg

I really like those vertical front grip\bipod combos, but I've got nowhere to mount it. Does anybody make a Picatinny rail that clamps onto a barrel so I can mount a vertical grip to distribute the weight evenly?

skscj
10-13-2009, 3:35 PM
Try a 4 rail gas block.

technique
10-13-2009, 3:40 PM
A barrel mounted VFG will affect your accuracy...well, just about any barrel mounted accessory(esp one you apply pressure to- bipod, VFG, sling mont.sling)

Just an FYI...it will kinda cancel out your free float. Food for thought, don't let it stop you.

dcbiii
10-13-2009, 3:42 PM
Try a 4 rail gas block.

Any old one will work with my gun?

UTG makes a cheap one, so for instance:
http://ecx.images-amazon.com/images/I/515QyK-4yXL._SS500_.jpg

Will work for my gun and barrel OD?

dcbiii
10-13-2009, 3:43 PM
A barrel mounted VFG will affect your accuracy...well, just about any barrel mounted accessory(esp one you apply pressure to- bipod, VFG, sling mont.sling)

Just an FYI...it will kinda cancel out your free float. Food for thought, don't let it stop you.

Good to know. The poster above noted that I could change my gas block to one that has quad rails....will this affect accuracy?

Thanks for the help guys.

Josh3239
10-13-2009, 3:45 PM
I believe your bull barrel needs .936, the standard gas block is .725. Something like will work: http://www.midwayusa.com/viewProduct/?productNumber=188739

Like Tech said, barrel mounted anything will cancel out the free float tube and negatively affect the barrel harmonics.

tomd1584
10-13-2009, 3:46 PM
please dont put that UTG on your rifle!

Josh3239
10-13-2009, 3:47 PM
Good to know. The poster above noted that I could change my gas block to one that has quad rails....will this affect accuracy?

Thanks for the help guys.

No gas blocks won't make a difference themselves. But if you attach something to the gas block (that is attached to the barrel) and you move that something it will effect the barrel. No your groups won't open up wild, in fact you probably won't notice a difference unless you are benchrest shooter who is trying to get the best accuracy he can.

technique
10-13-2009, 3:48 PM
Good to know. The poster above noted that I could change my gas block to one that has quad rails....will this affect accuracy?

Thanks for the help guys.

Yup, it is clamped to your barrel so anything you mount to it may affect your accuracy....it may be an ever so slight change. With a VFG you are now pulling on your barrel...it could shift your point of impact, same with a bipod. Its like resting your barrel on sandbags instead of resting on the free float, it messes with "barrel harmonics"....It may or may not be noticed until you shoot out to greater distances.

dcbiii
10-13-2009, 5:10 PM
Thanks for the info guys, you guys are great!

Codelphious
10-13-2009, 7:01 PM
please dont put that UTG on your rifle!

What's wrong with UTG? While I wouldn't condone putting a rail on a free-floating barrel, I don't know why the brand makes a difference here.

Is UTG's aluminum or quality assurance somehow inferior? Because if they're using CNC machines, as I have no doubt they are, I don't think you can fault the craftsmanship.

If there is factual evidence to the effect that their aluminum is of poor quality I'd really like to know, because I definitely don't want faulty products on my battle-ready rifle.