GreenWolf70
Junior Member
Lead From the Front
Posts: 45
|
Post by GreenWolf70 on Dec 13, 2011 7:43:46 GMT -8
Which is better, clamp style or set screw?
With the set screw I would be drilling locating dimples. How would you prevent the gas block from moving on a clamp design? Does either design offer a better seal on the gas port than the other?
Yankee Hill, Mid-West, EGW, who makes the best low profile GB, or is there any significant difference between them?
|
|
|
|
Post by bhwoodsman on Dec 13, 2011 10:22:29 GMT -8
A good topic for discussion for newbies and us curmudgeons.
I too have some considerations for future builds and the modification of one exiting upper. So far I've been led by what information I gleaned from others and and my own take based on what seems logical.
So far I've stayed with YHM steel with two or four rail config (you know to mount a bipod or a front sight). They are of two piece design pulled together with 4 cap head screws. But what do I know? They are heavy and I've learned I don't need all the rails - two or four. Now, I'm looking to go with gas blocks period. No base for any other purpose. Looking to go strictly with free float handguards with the gas blocks under.
I've always prepared the barrel and the gas block as I would for scoping one of my heavy magnum bolt guns.
I'm told steel is preferrable to aluminum to better resist erosion giving longer service. So what material and how fastened - pinch, clamp, or set screws for reliability, durability, barrel accuracy?
|
|
GreenWolf70
Junior Member
Lead From the Front
Posts: 45
|
Post by GreenWolf70 on Dec 13, 2011 10:41:03 GMT -8
Since you brought up free float handguards, what lengths are needed to cover carbine, mid and rifle positioned gas blocks? And I, too, don't care for all those rails, just want one rail all the way across the top and some small ones I can apply where I want them, but most important I want a handguard that is comfortable to hold. At the moment that hand guard would appear to be something like the Troy TRX Battlerail, or Samson Evolution.
It appears that the lo-pro gas blocks I am looking at are 4140 steel.
We could also add the best method to install each type of GB.
|
|
|
|
Post by letaz77 on Dec 13, 2011 23:21:14 GMT -8
Excellent choice with either Troy or Samson free floating hand guards. They are considerably lighter than the quad rails and easier to get used to.
On regards to clamp on vs set screwed...IMHO, your pick is as good as any. They both perform quite well. I have both types. The set screw is a low profile PRI stainless steel and it works flawlessly; no gas leaks, rock solid on the barrel and it was a brease to install with a pre dented barrel. The clamp on is Adams Arms Piston System. It has no leaks either but I needed a little more time to install.
Personally, I don't know much about adjustable gas blocks (other than the piston system I have) so I will not attempt to open that pandora's box. But either one should work very well.
|
|
|
|
Post by bhwoodsman on Dec 14, 2011 8:29:53 GMT -8
I'm thinking any of the steel low profile will be fine. With no other loading on the block to twist or pull it, and tucked under a free float, it will not move if fastened securely. I am not going to worry about dimples in the barrel to match the set screws if that is the way I'm going. Set screws (cupped, pointed and hardened) can be used and there are some very good thread sealants available. Remember, you may need or want to take it apart some day. I do wander if the clamp type, you know with the split, but they don't seem to be as compact or light.
This still doesn't answer my questions on the the attachment method vs. accuracy. Sure hoping to hear some experiences to save some money and time.
The length of the handguards seems to be up to the individual and the purpose. My long heavy barrel .223 rifle length gas is going to get a 15" so I can mount a bibod attach stud well out there for a better hold for me.
|
|
|
|
Post by GLSHOOTER on Dec 14, 2011 9:58:15 GMT -8
I'm thinking any of the steel low profile will be fine. With no other loading on the block to twist or pull it, and tucked under a free float, it will not move if fastened securely. I am not going to worry about dimples in the barrel to match the set screws if that is the way I'm going. Set screws (cupped, pointed and hardened) can be used and there are some very good thread sealants available. Remember, you may need or want to take it apart some day. I do wander if the clamp type, you know with the split, but they don't seem to be as compact or light. This still doesn't answer my questions on the the attachment method vs. accuracy. Sure hoping to hear some experiences to save some money and time. The length of the handguards seems to be up to the individual and the purpose. My long heavy barrel .223 rifle length gas is going to get a 15" so I can mount a bibod attach stud well out there for a better hold for me. I've shot gas blocks that were split, set screwed, pined and every other way except glued. No difference in accuracy. You aren't moving metal up in to the bore with the dimple/set screw approach and with the others the force is pretty equally applied. The quality of the barrel will be the biggy not how you mount the gas block. Greg |
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Dec 14, 2011 15:52:42 GMT -8
If clamp on gas blocks are available why not to use them?. Why to stress the barrel with set screw or make cuts to put pins?
If one wants to make everything possible to maximize accuracy staring with proper tolerances and a good barrel why not to continue this course?
The most accurate ARs I have seen, those used in matches and in high power competitions they use clamp-on gas blocks. There is a reason for that.
I am in the same page with Bob Whitley on this one.
...I mean is not like you have to spend extra to get a nice clamp on gas block.
|
|
|
|
Post by guncollector on Dec 15, 2011 1:39:36 GMT -8
I my experience clamp on gas blocks have been better. I have had small gas leaks around a set screw gas block. Never had any leaks with a clamp on one.
|
|
|
|
Post by bhwoodsman on Dec 15, 2011 6:33:01 GMT -8
Thanks for sharing your experiences and findings.
In my initial builds, I was led to believe clamp-on was the only way to go. I would never drill or dimple a barrel for set screws in a gas block.
|
|
GreenWolf70
Junior Member
Lead From the Front
Posts: 45
|
Post by GreenWolf70 on Dec 15, 2011 9:52:07 GMT -8
LOL, withing hours of you posting this, the place I was looking at for good cheap gas blocks sold out of their clamp on gas blocks, so thanks.
|
|
|
|
Post by sandsock on Dec 18, 2011 14:46:08 GMT -8
If you have a choice, go with a clamp set up. If you have to use a set screw then I would recommend the type with two screws and carefully put a couple locating dimples or have someone mill a slot to keep it from moving. You can also measure the OD of your barrel and the ID of the gas block to get it as tight as possible (allowing for the added thickness of a finish) but as most clamps are really only marginally more expensive than set screw versions by the same manufacturer, you'll come out ahead generally with a clamp and dimensionally (since it will likely be from a manufacturer other than the barrel) they will be more forgiving and less hassle in the end.
|
|
