JMoto

Oh, sorry. I figured it would be easier than having folks dig through multiple pages to find it. If it needs to be in a new section or something, feel free.

I edited my first post with all of the info and pics unless I forgot to press save lol

Review is up, I think I have sun stroke so please forgive me if it is scattered about a tad. There is a possibility some of it is in German, Japanese, Spanish, and Gibberish. If so I will correct it later.

I am absolutely beat, my review will be pushed off until tomorrow night after work. It handled the handloads better, but my new extractor has a burr on it which was sort of eating the rim on extraction. It was not too bad, the brass is still usable.

432 rounds at time of failure. I am off to the range and we shall see what happens.

Yeah, I had to trim a bit off of the buffer so that there was a bit of a gap for the bolt stop. There was a hair of clearance but I wanted a bit more. I am still a bit shy of the gap the instructions recommended but i the part does not do what I wanted then I still have an "almost spec" buffer.

I had the same suspicions, but have not confirmed it. The dimensions they have for their adjustable version are very close, but because of the shelf for the adjustment screw it will not fit under the factory sass tube. Vtac lists the ID as 1.75 which is the same as the AR-15 tube. If that is the case it is a no-go but in addition to that , it is not centered on the nut so that ID may be irrelevant. OK my brain hurts. edit, I have read every article on this board in regards to this subject, that is the original reason I had joined.

The PRI running a straight tube. I am running vtac/jp on some of my AR rigs but have yet to make the switch on the 308 caliber rifles. I get conflicting info from everyone.

is thee any chance of getting an ID measurement? I am wondering if it will clear a particular gas block.

Correct, you CANNOT shotgun/break the action by simply pulling the the rear pin. The front pin MUST be removed so you can slightly pull the upper forward in order for the CWS to clear. It is only .08 in but it is enough to prohibit standard breakdown. I used a poor term when I said "service rifle" I meant a rifle used my members of the armed services and the like. I should probably have said "combat rifle" I think this would help with the buffer being beaten up as that is generally caused by excess gas in the system forcing the buffer to get torn up by the carrier striking it with excessive force. The system staying "locked" longer may give the gas more time to dissipate. Over thinking it, this extended lock time may also allow for a more linear movement of the carrier because the bolt and carrier are not fighting to extract the brass before it has contracted from the walls of the chamber.

The problem I am getting is with factory loaded FGMM and others. The rim is getting beat up, I am actually in the process of getting photos of my brass before the installation, tanks for reminding me. This also caused premature extractor failure. I was just starting load development when the failure occurred, but looking back at brass from factory loads showed me that I had gotten lazy during my inspection process with factory loads as well. I will share my load data in this thread as well.

Ok, I should be out to the range either Sunday or Monday and the review should be up the same day.

TUBB CWS (carrier weight system) Reason for my purchase: I own a DPMS SASS and was having issues with timing/extraction. I was getting an aggressive extractor mark on all cases. I ran 400 rounds of factory match ammunition through the rifle, all of which displayed this mark. 32 rounds later (load development) I was getting pulled rims and eventually the extractor broke on round 432. In the process of handloading I was also getting some casehead swipe at what I felt was a relatively low load of 43 grains of varget. Now on to the review itself The product itself comes in and looks simple enough, but after looking at it I see something that can be a no-go for certain users. I will go over that later. Here is all of the stuff that comes in the packaging. Woo Hoo INSTRUCTIONS The installation is easy enough, it fits into the bolt carrier and whichever weight you use slips into the back. No screws and no clips to break, lose or fall off. I like this! Here is the part i do not like. If you look you can see there is something sticking out .08 inches. That is the flange that holds the weight. This is needed so the weight holder is not flopping around and doing things it is not supposed to do. At the range: I did not take any pictures at the range because I truly hate those guys who take pictures of their own guns at the range. It has benches and target stands and rangemasters, move along, nothing to see here. I did not notice any change in recoil with the CWS and there were no changes to the function of the rifle. I put 50 rounds downrange and experienced no failures related to the CWS. I tried out a C-products mag and had a failure to feed on round three with factory match ammunition. I single loaded during my testing of the handloads. So in my case there was no adverse effects as far as reliability was concerned. After the range The case on the left is a factory piece of gold medal match 168gr. Take note of the heavy extractor mark. The case on the right is a handload of 44.3 gr of varget with a 168 SMK. Notice that the extractor mark is there, but much less pronounced. You can also see there is a "swipe" on this same case. I am not sure where this came from, I pulled the extractor assuming there would be a burr on it but there was not. On the left you have a piece of FGMM brass, 43gr varget 168 SMK. Look next to the FC headstamp and you will notice a "smear" this is casehead swipe caused by the case being forced up against the bolt face/ejector while the bolt is rotating to eject the case. This was fired prior to my initial extractor failure and was prior to the CWS installation. The case on the right is post CWS install and was 44.3 gr of varget. So here we had more pressure and a smaller amount of casehead swipe. I feel this is indicative of the CWS allowing chamber pressure to decrease IE increasing lock time. This is one of the things it was designed to do. Here is another photo of the "smear" on the outer edge of the rim that did not occur until the new extractor and CWS install. It really stands out on the dirty brass but it if very hard to feel, but it is there. I was baking in 90+ degrees of sun for a few hours and did not have enough sense to pull the CWS out and see if it changed that "smear" at all. CLIFF'S NOTES CWS does increase lock time, allowing chamber pressure to drop and allow the case to be released from the chamber without causing undo wear on the case/extractor CWS does not (in my case) cause any ill effect on the physical function of the rifle If I had it all to do over again, I would probably have put an adjustable gas block on the rifle... oh wait, I have a DPMS SASS and no infinitely adjustable gas block on the market will fit it. This will do, but it is not ideal for me personally. I have a feeling that with a rifle length gas system the CWS would make the recoil impulse more linear and make the recoil feel lighter. If the 308 AR platform is anything like the smaller platform with midlength or carbine gas systems 90% of the gas could be blocked and the rifle would still cycle with full loads. NOTES FROM THE AUTHOR: The one thing I do not like is that you can no longer pull the rear pin ALONE to service the rifle. If this is your duty gun or your fightin' gun do not use this product! You will need to pull both pins and finagle the upper off. I tried it on several AR rifles and all of them had to do this. I could force it ON a couple but it is not ideal, and you certainly could not manhandle it off as it would put unwanted force on the front part of the receiver that holds the cross pin. On some AR lowers this are is very thin and we would not you to die because you had to fiddle with a rifle that failed. I am a firm believer that your duty gun/service rifle should be easy to service and you should train for failures. This part WILL INCREASE the time it takes to do an emergency bolt swap or clear a blown primer from your rifle. My extractor: After looking at my brass i thought there was a burr or rough edge on the extractor that was disfiguring the rim, but after pulling it off of the bolt I see no such burr. This extractor is actually much nicer than my factory unit which had several sharp edges. here is what extractor failure does to your cases

Mine will be here tomorrow, I will report back with results.

What gasblock did you use?

Welcome to the site, there is some pretty good info here.

Yes, I said sparingly. Too much lube and you won't feel anything when you stroke the press... <dontknow> In all seriousness, when converting 30 cal brass to 44 auto mag the old rcbs stuff is the only stuff I know of that will net get cases stuck in the forming die.

I like the dillon spray in the pump for most jobs. If it is something hard to size I will use the old formula rcbs stuff on a pad. I only have 2 tubes of it left so i am using it sparingly.

Stuff just started jumping into your cart didn't it?

There was a write up in the shotgun news about the LB rifle. The only thing I noted was the nylon rifle length buffer.

Just to clarify, you were able to get the JP ADJUSTABLE gas block to fit with the JP hand guard? I am looking at doing this with my DPMS SASS but after looking at the measurements I thought it would not fit. On JPs site, it lists the handguard inside dimensions for the 308 to be 1.75in which is the same as the AR-15 rail.

On snipers hide they have a 5 shot min. and you must show the entire target. There may be more rules but I dOnt recall

I found this site looking for some info on adjustable gas blocks and a few other things related to my DMPS SASS and found so much good information that I decided to join. I hope I can be somewhat helpful as well as learn some more about the platform. To the owner, thank you for such a great site. It is difficult to find good data on other forums without digging through a bunch of unrelated posts.

First post, still doing a lot of reading. I have some catching up to do around here. These pics are from a range day in February of last year. I have not had much time to shoot since then. I was Doing some load development and suffered a broken extractor and a loose scope ring... how embarassing. I hope to be back out there soon. I am not sure if you guys have any rules about posting group shots, these are three shot groups. I have since changed to 5 shot groups as I am working on not "wishing" the 5th shot in. If there is a min. shot number required I can delete the post. The Rig My personal best with any rifle (yes that is a 3 shot group) Specs on the rig are as follows DPMS LR-308 S.A.S.S. swapped out the PSG-1 grip for an ergo ambi (my favorite AR grip) bedded receiver Armalite cantilever 30MM mount Nightforce NXS 3.5-15x50 HSM .308 168 gr HPBT match ammo I ran some federal gold medal match and as usual the groups were larger than with the HSM, this rifle loves the stuff. Now that she is functioning correctly I can finally develop a load for it. I have only been waiting 15 months!