archangel2003

Yeah, I snatched them out of the wife’s purse and she never noticed them gone!

It's still not as hard to remove off the Delta Ring as the same setup on the AR-15, but not nearly as easy as it used to be. I'm tempted to trim the back end under the AR-15 Delta Ring to make removal more reasonable.

OK, I took the advise and pulled out the razor knife, files and used the belt grinder. First 2 pictures. I took the all the internal parts off the back end where the hand guards locate under the Delta Ring. Next 2 pictures. I then ground the front inner tabs level with the outer tabs, then took down the triangle end cap to match and the second is it installed. Next Picture. All that was not enough so the part that the delta ring grabs that were too long were shortened. Next 2 Pictures. The retaining tabs for the delta ring were still in the way so off they came. Yeah, with the hand guards off the delta ring and spring will be loose but not something I'm worried about. After all that, they now fit, just don't look too close when they are apart. The last picture is it installed at the Delta Ring.

If I were to mark the gas tube as it's mounted, then take the gas block off and push the tube in further, how much free play/clearance should it take up before touching the bolt gas tube receiver? Also, to measure the gas port location on the barrel, what is the reference point we measure from? In my case, the gas port would need be to be further away from the chamber making the gas tube possibly hit if it were too close.

Every source I found says that the gas tubes for the AR-15 and the AR-10 are the same length no matter the gun length/size.

OK, I found a post listing various barrel nut threads.

There are so many times throughout my life where I made permanent modifications to something only to find out it was something else and could not put back what was ground off. Rsquared, I would much appreciate some measurements for verification. It might not answer my question directly, but more info is better than not knowing. I would love to have one of each barrel nut, DPMS, AR-10, and any others that might be different so we can verify what is and is not compatible. With my luck, the guy who received the pallet of boxed parts accidentally put an AR-10 barrel nut in the DPMS barrel nut box and the parts picker either did not know the difference, or just did not notice.

My first few drawings were so bad I tossed them as I did not want it to look like a 5th grader was building an AR-10

The heat shields are no issue, but I would have to remove so much that there would be nothing left on the front to mount to. AND, there are mid length gas system AR-308 uppers that have my style of hand guards. BTW, it's a "DPMS 308 A3 UPPER RECEIVER"

I first ordered the round ones, then, when they did not fit I "found out" (AKA, read the info in them) that these hand guards use the triangle end caps, so now I have both types. The only non-free float hand guards I see are the MagPull ones and they are not pretty. I just wanted the plain ones. The nearest gun manufacturer to me is R-GUNS in Carpentersville, IL, so next time I'm in the area, I'll stop by and bug them in person. One way or another, I'll need to have some type of hand guard and do not want to spend the prices they want for the free float ones.

If I knew of someplace that sold that hand guard for the AR-308, I would get it, but as far as I can tell, mid length is mid length and not AR-15 or AR-10, it just seem as if they are just the same. Here is the look I was going for.

I know the difference between an AR-15 and the larger AR-10 with a larger diameter barrel, larger threads and what not. The gas systems on both my rifles (AR-15 & AR-10) is mid length, and they both use the exact same gas block, the exact same gas tube and they both fit perfectly. I did not want a free float hand guard and was looking for the stock vented hand guard that was not the triangle style. The first one I ordered was the about same diameter, but without the taper it looked a little clunky, then I found these with a slight taper and they look just right. All three fit the AR-15, but are a TOTAL PAIN to remove as the delta ring it so tight, as if the mounting serrations are deeper into the delta ring gap The AR-10 shows the serrations higher up in the delta ring gap and is much easier to remove and install. I just need to have someone who used a mid length gas system and slip in hand guards so I can know what barrel nut works. I'm assuming it's the barrel nut that I'm having issue with. The bottom fits perfectly, and the top fits perfectly, the issue is the hand guard is about .200 to .250 too long so the top and bottom don't fit at the same time.

Yep, it looked to be somewhere in the 1/4 area. The question is why? I looked at the local gun stores and non had a DPMS 308 barrel nut, or any barrel nus of any kind. They had stripped lowers and the parts for them, stripped uppers, and all kind of other parts, but no barrel nuts.

Yeah, it's a cross section of the barrel nut with the .733 measurement being the inner threads. I refer to the left side as the front. The .121 measurement width is the serrations that the hand guard mounts to and if it were so that the front of the .121 measurement were at the back of the .125 measurement (.250 back from the face) it would align for the hand guard.

Here are my measurements.