Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide

Gas tube and block


Recommended Posts

I have a PSA PA10 G3 that came with the old style M16A2 style handguards and front sight both of which I am replacing. From what I have been reading, the PA10 requires handguards that are "DPMS low." I found a set of handguards made by Presma that are 15" entitled "AR10 LR 308 Super Light M-LOK Series Free Float Handguards, DPMS Low Profile" (https://team15tactical.com/products/presma-ar-10-lr-308-super-light-m-lok-series-free-float-handguards-15-in-dpms-low-profile) that I think should work for my purposes. My main question pertains to what else I will need to purchase and install. The handguards come with a new barrel nut, but nothing else regarding installation parts. I am assuming I will not need to replace the gas tube, but I am not entirely sure what gas block I should use. There are several low profile gas blocks on the market in .750 including some that are fixed and others that are adjustable. PSA does not provide the specifications for their barrel, but all that I have read indicate a .750 barrel for the PA10. I would appreciate any information regarding whether or not the gas tube needs to or should be replaced as well as information concerning the appropriate gas block. Lastly, are there any advantages to having an adjustable gas block versus a fixed one? Below are a couple of links to .750 gas blocks that are sold by PSA with the first link being the gas block that comes standard with PA10's that come with their free float handguards. I primarily bought this rifle for home defense and occasional time on the range. Thanks!





Link to comment
Share on other sites

You don’t need to change your gas tube. Adjustable gas blocks are needed for running suppressors. If you don’t plan on doing this then no, you don’t need one. One thing we would request you do while it’s apart is measure gas port diameter. Also give full measurements on recoil system. Read up on threads here to find out why.

It’s your rifle so you use it how you deem fit, but.... 308AR rifles are not home defense rifles unless you own a ranch in Montana. You will over penetrate anything you shoot at and it will go through your target, your house, the neighbors house and the house next to it if it doesn’t hit a solid steel object. Just saying, in case you didn’t think of that.

Link to comment
Share on other sites

Thanks for the information. I know a 308 can be a bit much for home defense and it would likely be my last go to out of my choices in the house. Mainly, I wanted another AR platform in a caliber other than .223. Just the same, I intend to outfit this one so that it can easily be used for longer shots at the range as well as at home if the need arose. Fortunately, I do live in the country so there are no neighbors to fret over. I'll stick with the gas tube that came with the rifle and it sounds like any fixed low profile .750 gas block should work fine for my purposes. I'll check out the threads on gas port diameters and recoil systems as well; thanks again.

Link to comment
Share on other sites

Ok we need more information. Pics would be good too. How long is the barrel etc. I did exactly what you are talking about. I needed to acquire a Armalite carbine 308 gas tube to have the proper length gas tube. A standard 3/4" gas block is what I used. I do not recall if my rail is DPMS hi or low I will check it out when I get home. This was w/the20" barrel upper they sell. I am pretty sure you want a DPMS high rail but I will check in the am.

Link to comment
Share on other sites

Below is the response I received from PSA when I inquired about the fit of the Presma handguards I ordered. Essentially, they state the PA-10 is DPMS low, but they won't guarantee the fit of any parts other than their own. I'll find out if they fit once they arrive tomorrow either way.

"While the PA-10 platform is loosely based on the DPMS gen1 low profile, we can only guarantee the fit and function of PA-10 parts to other PA-10 parts and we do not recommend mixing AR-10 manufacturers. If you have any additional questions or concerns, please contact us".

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...