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Addax
06-04-2008, 11:35 PM
Well, I went out to the range and shot some test targets with my RRA NM Gas Piston Upper conversion.

I did not spend allot of time dialing in the scope, I just shot at 2 test paper targets at 100 yards, but I was pretty impressed with the results, and I thought I would share.

I am going to spend a little more time at the range next time with some match ammo and see what I can really do with this upper.

RRA NM Upper PWS Gas Piston Conversion
PWS Stainless DNTC Compensator
Stag Lower with NM LPK
Magpul PRS Stock
Standard Rifle Length Buffer
Hi-Lux 3x-9x 40mm Obj. scope / 30mm rings
Federal XM193 55grain ammo
Sand Bag Rest
5-6mph crosswind at Angeles

http://i216.photobucket.com/albums/cc137/addax/103_0749.jpg

http://i216.photobucket.com/albums/cc137/addax/103_0748.jpg

http://i216.photobucket.com/albums/cc137/addax/103_0747.jpg

Q
06-05-2008, 12:03 AM
sweet looking rifle. I want to build my N6 like that.:cool:

Addax
06-05-2008, 12:59 AM
Thanks.

When we get things going on my end, lets talk.

sweet looking rifle. I want to build my N6 like that.:cool:

norcal-ar
06-05-2008, 5:34 AM
is that a 20" barrel?

Addax
06-05-2008, 7:12 AM
20" Wilson Air Gauged 1/8 twist barrel with Wylde Chamber.

It is a full RRA National Match Upper, the NM A4, that I converted to a Gas Piston System.

is that a 20" barrel?

Army GI
06-05-2008, 7:13 AM
Pfft. Totally missed the dime :rolleyes:

Addax
06-05-2008, 7:19 AM
For a quickie first accuracy test, and trying to dial in my scope in, I have to say it is not a bad start..;)

Pfft. Totally missed the dime :rolleyes:

Army GI
06-05-2008, 1:00 PM
It's a joke, man. Nobody ever hits the coin.

Addax
06-05-2008, 1:04 PM
Yeah, I know you were joking around, but it would sure be nice to hit the coin.:43:

I should try to set up a test target like that... Put a dime in the center bullseye...

It's a joke, man. Nobody ever hits the coin.

SuperSet
06-05-2008, 1:08 PM
Good shooting, bud!
If you can answer, have you seen any signs of carrier tilt for that piston setup?

GenLee
06-05-2008, 1:11 PM
Nice job and WOW a sweeet build.

Addax
06-05-2008, 1:38 PM
Thank you, and Good Question.

With my PWS Gas Piston System builds, we have not noticed any significant bolt tilt/bolt carrier tilt-tipping.

I am not going to lie and say, there is absolutely no bolt tilt, but honestly we have not noticed any excessive wear patterns to indicate excessive bolt tilt, and to me this is totally acceptable.

I have shot over 2000 rounds in one of my test units and 600 rounds in another test unit, and so far I have not seen any excessive or weird wear marks in the upper receiver, nor the front edge of the buffer tube or on the bolt head lugs.

The NM Upper has about 100 rounds through her, and nothing to indicate any bolt tilt.

I have a POF Gas Piston Upper with over 1300 rounds, and I have weird wear on the front edge of the buffer tube, where it has worn down to white aluminum. This is where the Bolt Carrier Assembly hits the buffer tube due to bolt / bolt carrier tilt-tip.

Plus I have noticed some of their super slick coating wearing off in small areas of the upper.

Keep in mind that all of the Gas Piston Systems and Rifles on the market are all a little different, and some other designs are known to have excessive bolt tilt, but I will say again, that the PWS system does not show any weird wear patterns or any symptoms of excessive bolt tilt.

One more thing, the PWS design in turn minimizes bolt tilt since the oprod and bolt carrier are bascially one piece, like many other advanced designs like the SIG556.

The other designs like the POF, Osprey, LWRC that have a seperate non-connected op-rod that hits or hammers the top of the bolt carrier, will induce bolt tilt.


Good shooting, bud!
If you can answer, have you seen any signs of carrier tilt for that piston setup?

Addax
06-05-2008, 1:38 PM
Thanks Gen Lee.

How's that AR working for you? You know I still miss her..;)

Nice job and WOW a sweeet build.

Army GI
06-05-2008, 1:41 PM
Yeah, I know you were joking around, but it would sure be nice to hit the coin.:43:

I should try to set up a test target like that... Put a dime in the center bullseye...

Haha, I already tried that. Unless the target is backed with wood, the coin will just be punched right through the paper by the bullet and leave a dime sized hole in your target:p

Addax
06-05-2008, 1:45 PM
LOL, yeah, the targets at Angeles are cardbord on PVC Pipe frames, so I would need to make some sort of makeshift wood block to back it up it if were to do that.. Good Point.





Haha, I already tried that. Unless the target is backed with wood, the coin will just be punched right through the paper by the bullet and leave a dime sized hole in your target:p

mikecro1
06-05-2008, 1:56 PM
What addax is saying bellow is % 101 ...I have a PWS All Cmmg build that has seen over 1500 rds with no weird marks, or failures...it has worked flawlessly...I will never go back!

...unless ofcourse anyone would like to give me a FREE DI based rifle:p

Thank you, and Good Question.

With my PWS Gas Piston System builds, we have not noticed any significant bolt tilt/bolt carrier tilt-tipping.

I am not going to lie and say, there is absolutely no bolt tilt, but honestly we have not noticed any excessive wear patterns to indicate excessive bolt tilt, and to me this is totally acceptable.

I have shot over 2000 rounds in one of my test units and 600 rounds in another test unit, and so far I have not seen any excessive or weird wear marks in the upper receiver, nor the front edge of the buffer tube or on the bolt head lugs.

The NM Upper has about 100 rounds through her, and nothing to indicate any bolt tilt.

I have a POF Gas Piston Upper with over 1300 rounds, and I have weird wear on the front edge of the buffer tube, where it has worn down to white aluminum. This is where the Bolt Carrier Assembly hits the buffer tube due to bolt / bolt carrier tilt-tip.

Plus I have noticed some of their super slick coating wearing off in small areas of the upper.

Keep in mind that all of the Gas Piston Systems and Rifles on the market are all a little different, and some other designs are known to have excessive bolt tilt, but I will say again, that the PWS system does not show any weird wear patterns or any symptoms of excessive bolt tilt.

Solidsnake87
06-05-2008, 6:51 PM
Nice rifle! Shoot better ammo though. Get some federal gold. With a some pratice you should be shooting groups not over 1 inch at 100 yards.

ar15barrels
06-05-2008, 7:49 PM
Here is a perect example of vertical stringing:

http://i216.photobucket.com/albums/cc137/addax/103_0747.jpg

Addax
06-05-2008, 7:56 PM
Yup, good match ammo and a little more time with her is what I need.

Oh, and I probably should not have a Starbucks Venti Americano before hitting the range...:D


Nice rifle! Shoot better ammo though. Get some federal gold. With a some pratice you should be shooting groups not over 1 inch at 100 yards.

Addax
06-05-2008, 7:58 PM
Actually that was me trying to dial in the scope and I must admit I was also trying different stock positions with the PRS stock.

I was taking my time between shots, so if there was any vertical stringing that is my fault.


Here is a perect example of vertical stringing:

Addax
06-05-2008, 9:02 PM
Nice... Any pics?

What addax is saying bellow is % 101 ...I have a PWS All Cmmg build that has seen over 1500 rds with no weird marks, or failures...it has worked flawlessly...I will never go back!

...unless ofcourse anyone would like to give me a FREE DI based rifle:p

maxicon
06-06-2008, 9:26 AM
I'd be surprised if that group with the flyer is representative of what you (or anyone) can get with XM193. The spec for M193 is for a mean radius of 4" at 200 yards using 3 10 round groups. According to Hatcher, edge to edge group size is roughly 3x mean radius, so that's about 6 MOA spec.

Assuming some lots will come in under spec (but given cost controls and high volume production, not much under), getting repeatable 10 round 2" groups at 100 yards from XM193 is possible, but pretty rare. 3" is much more likely, in my experience. The manufacturers just aren't going to be making M193 at 1/3 the accuracy spec out of the goodness of their hearts.

Match ammo and handloads are a different matter, of course, but no matter how good the rifle is, you can't shoot smaller groups than the ammo's capable of.

Some 10 round match ammo groups would be a much better representation of the rifle's capability!

GenLee
06-06-2008, 9:49 AM
Thanks Gen Lee.

How's that AR working for you? You know I still miss her..;)

I bet you do, I have built two others since buying her from you and she is still my favorite.:D Never a sigle hickup after around 2K rounds, You did a fine job on her. I am waiting for your site to finish so I can enter the AK owners association...

Addax
06-06-2008, 2:50 PM
Cool, I am glad to see she is serving your well.

I am working on the website, not too much longer.. Just working out some kinks.

We will help you out on the AK parts/accessories, no problem.

I bet you do, I have built two others since buying her from you and she is still my favorite.:D Never a sigle hickup after around 2K rounds, You did a fine job on her. I am waiting for your site to finish so I can enter the AK owners association...

Addax
06-06-2008, 3:35 PM
The shot groups on both targets is what I could pull off with the rifle using Federal XM193 55grain brown box Lot# 141 and Lot#201.

I was taking my sweet time between shots, and I was only using 2-3 rounds per mag.

I have shot 1-3" 100 yard groups of 3-4 rounds using the same ammo with a Stag 16" Upper in the past, but I also had 3+"-5" flyers too, so I know what you are saying that getting consistent tight groups like this using XM193 is surprising, but I am here to tell you I did it.

You are right, I also believe that this uppers/rifles accuracy will be better represented with some nice Match Grade ammo.

I am also going to take my precision shooting stand with me next time so I am not fiddling around too much.

I already ordered .223 Federal Match 69 Grain Boat Tail Hollow Point Gold Medal Match ammo (several shooters recommended this ammo to me) and I am going to pick up a higher powered scope this week.

Hopefully I will be able to get some range time in next couple of weeks since I am launching my new website next week (finally after several months).

I will also snap some pics at the range too.


I'd be surprised if that group with the flyer is representative of what you (or anyone) can get with XM193. The spec for M193 is for a mean radius of 4" at 200 yards using 3 10 round groups. According to Hatcher, edge to edge group size is roughly 3x mean radius, so that's about 6 MOA spec.

Assuming some lots will come in under spec (but given cost controls and high volume production, not much under), getting repeatable 10 round 2" groups at 100 yards from XM193 is possible, but pretty rare. 3" is much more likely, in my experience. The manufacturers just aren't going to be making M193 at 1/3 the accuracy spec out of the goodness of their hearts.

Match ammo and handloads are a different matter, of course, but no matter how good the rifle is, you can't shoot smaller groups than the ammo's capable of.

Some 10 round match ammo groups would be a much better representation of the rifle's capability!

mikecro1
06-06-2008, 6:01 PM
Nice... Any pics?

...right here...

http://i29.photobucket.com/albums/c265/urban_jedi/IMG_1467.jpg

maxicon
06-09-2008, 10:16 AM
The shot groups on both targets is what I could pull off with the rifle using Federal XM193 55grain brown box Lot# 141 and Lot#201.

I was taking my sweet time between shots, and I was only using 2-3 rounds per mag.

I have shot 1-3" 100 yard groups of 3-4 rounds using the same ammo with a Stag 16" Upper in the past, but I also had 3+"-5" flyers too, so I know what you are saying that getting consistent tight groups like this using XM193 is surprising, but I am here to tell you I did it.

You are right, I also believe that this uppers/rifles accuracy will be better represented with some nice Match Grade ammo.


I'd be interested in seeing how it does with 10 round groups with XM193. It would be good to see how they compare with the premium ammo, as well.

I can do OK sometimes with small groups on XM193, but it's pretty rare for me to get a 10 round group smaller than 3" from a gun that shoots much better with match ammo.

Addax
06-09-2008, 11:22 AM
Yeah, we are going to go back and try to shoot 10 shot groups.

What we are going to do soon, is take a couple of my 16" Carbine Gas Piston Uppers we built for testing and the NM Gas Piston Rifle.

We are going to set up different targets after we zero the 3 rifles in (since I am procuring brand new scopes for them), we are going to set up test / group targets and shoot all 3 using XM193, PRVI 55grain, and Federal 69grain Match Ammo.

We want to see what kind of groups we can achieve at 50 yards, 75 yards and 100 yards for all 3 rifles documenting the different groups/ammo/variables etc.

If I can get out there on a Monday or Thursday I will set up paper at 300 yards for the NM using 69grain (but I also might look at a different round for this range, not sure yet).

Many variables come into play between rifles, ammo, scopes, mounts etc. etc.

As soon as I get out there and I can do this, and snap some photo's, I will post the results.

I'd be interested in seeing how it does with 10 round groups with XM193. It would be good to see how they compare with the premium ammo, as well.

I can do OK sometimes with small groups on XM193, but it's pretty rare for me to get a 10 round group smaller than 3" from a gun that shoots much better with match ammo.

ar15barrels
06-09-2008, 3:55 PM
we are going to set up test / group targets and shoot all 3 using XM193, PRVI 55grain, and Federal 69grain Match Ammo.

We want to see what kind of groups we can achieve at 50 yards, 75 yards and 100 yards for all 3 rifles documenting the different groups/ammo/variables etc.

Skip 50 and 75.
100 is the standard.
Some bullets, especially the long ones, are not even settled down yet at 50yds.

Cypriss32
06-09-2008, 4:13 PM
Try the 77gr BTHP Black hills stuff. It shoots good out of those barrels. I had the same barrel on my old AR, It was a shooter!

Addax
06-09-2008, 8:42 PM
Thanks guys.

Another member PM'd me about the same 77 grain Black Hills rounds..

Randall, I was thinking for the 16" carbines at 50-75 yards, just some close range work. You don't think it would warrant a close range accuracy shot?

If not, then I won't waste time.

ar15barrels
06-09-2008, 9:28 PM
Thanks guys.

Another member PM'd me about the same 77 grain Black Hills rounds..

Randall, I was thinking for the 16" carbines at 50-75 yards, just some close range work. You don't think it would warrant a close range accuracy shot?

If not, then I won't waste time.

Don't waste the time doing 50 and 75.
You can extrapolate backwards, but not forwards.
1 MOA at 100 will usually mean 1 MOA at 50, but 1 MOA at 100 will rarely mean 1 MOA at 200.

Addax
06-09-2008, 9:37 PM
Cool, Thanks, I will stick to 100 yards and if I can get there on the right day the 300 yard paper targets.

Don't waste the time doing 50 and 75.
You can extrapolate backwards, but not forwards.
1 MOA at 100 will usually mean 1 MOA at 50, but 1 MOA at 100 will rarely mean 1 MOA at 200.

BlackReef
06-09-2008, 9:45 PM
Awesome build Chris, like I said earlier, that thing is beautiful!

trinydex
06-10-2008, 4:39 PM
Haha, I already tried that. Unless the target is backed with wood, the coin will just be punched right through the paper by the bullet and leave a dime sized hole in your target:p

then you can say that's a 10 cent i mean shot group...