As my wife says...Gun Porn!
- Thread starter Beentown
- Start date
Sweet looking rifle, Sam. Nice build.
Dumb question... Difference between gas and "piston?" Both my guns have gas tubes (ones a RRA) so I assume they're gas?
Dumb question... Difference between gas and "piston?" Both my guns have gas tubes (ones a RRA) so I assume they're gas?
Ohiosam
*Supporting Member*
Basically a rod runs above the barrel from the gas block back to the receiver. On fireing the gas pushes the rod which forces the bolt back. This is the same way AKs, M1s, and M14s operate.
Direct impingement (gas) is the normal way ARs operate. A tube directs the gas from the gas block back to the receiver and a burst of gas forces the bolt back.
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Ahhhhh gotcha. So basically they're both gas operated, just in slightly different ways.
Ohiosam
*Supporting Member*
Ohiosam
*Supporting Member*
This link should tell you all you want to know about it. I know it has a gas block. Not sure if this is considered piston or not though. I do know it is a shooter and then some. More capable than I am. I'm not sure you can build one that I could shoot any better. I know a "better" one could be built. Just doubt "I" would be able to shoot it any better than this one. Sort of like having a 700HP or 750HP car. Could the "average person" really get much more out of the 750HP vs the 700HP? Probably not.
https://www.rockriverarms.com/index...tegory_id=567&CFID=592340811&CFTOKEN=48825920
Ohiosam
*Supporting Member*
Phil I believe yours is direct impingement not piston.
RRA's piston is called LAR-PDS. http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=442
I already have 2 regular ARs. I've been curious about piston rifles and found this upper at a reasonable price (for a piston). Complete piston rifles are expensive, I probably wouldn't spend the money they cost. I can play with this and if I don't like it probably sell the upper for most of what I paid.
RRA's piston is called LAR-PDS. http://www.rockriverarms.com/index.cfm?fuseaction=category.display&category_id=442
I already have 2 regular ARs. I've been curious about piston rifles and found this upper at a reasonable price (for a piston). Complete piston rifles are expensive, I probably wouldn't spend the money they cost. I can play with this and if I don't like it probably sell the upper for most of what I paid.
Ohiosam
*Supporting Member*
Ohiosam
*Supporting Member*
Yes. I shoot enough of them that I'm pretty used to them. I've learned their advantages in offhand shooting.
Ohiosam
*Supporting Member*
Thanks, I did make a few marks in the anodizing with the clamps and some from the chips spinning on the drill bits. Not terrible but I see them. All in all it's a pretty rewarding project.
So the stock RRA handguard on my X-series rifle was a bit too bulky for my liking. With the scope and the bipod, it just felt heavier than it needed to be. A few weeks ago I picked up a new lightweight free-float handguard made by Midwest Industries. It's a 15" SSK Keymod series to be precise. I didn't get a deal on it... It was expensive... But I wanted it, so it is what it is. Lol. Anyway, today I finally got around to making the swap. This was the first time I've attempted this. Thank God for YouTube. Lol. It was pretty painless actually. I did have some difficulties getting the stock locking ring to break free and also the barrel nut. Apparently Rock River is a big fan of thread-locker, because they had plenty of it on there! Some heat from a heat gun a few times and I was able to get everything broke free though. The new handguard went on easy-peazy.
Very happy with the change so far. It's noticeably lighter and does look better too, IMO. The new handguard has QD holes machined into it as well, so sling attachment is quick and easy, which I didn't have before.
Old handguard on the right, new one on the left...
Very happy with the change so far. It's noticeably lighter and does look better too, IMO. The new handguard has QD holes machined into it as well, so sling attachment is quick and easy, which I didn't have before.
Old handguard on the right, new one on the left...