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Sigless in
Indiana
Picture of IndianaBoy
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quote:
Originally posted by offgrid:
quote:
Originally posted by IndianaBoy:
quote:
Originally posted by offgrid:


I would like to see a gas block manufacturer come out with a drill to size block. Ship with a gas hole as small as .050, drill to size....



There was a guy who had a captive detent sliding plate system that could be drilled with three different port sizes.

It was a smart design. Guy had a death in the family and other priorities took him away from it I think. Can't remember the name.

I am half tempted to pull my 3-gun rifle apart today just to inspect the adjustment screw in my most heavily used rifle that as an adj gas block.


MicroMoa

Smart, simple design.

Found several of his post regarding gas port size. He still has a few videos on youtube. https://www.youtube.com/channe...RTBMGsZVXJBnPfk8VabA



That's the one!
 
Posts: 13565 | Location: The Edge of the Ozarks | Registered: December 04, 2003Reply With QuoteReport This Post
semi-reformed sailor
Picture of MikeinNC
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Originally posted by offgrid:
quote:
Originally posted by MikeinNC:

I’ve never had a problem with an adjustable gas block. I have a JP and one I made....once I get them set to run nato ammo with the suppressor and without, I lock it down and never fiddle with it again.


How many rounds?


At least 1k thru both...with and w/o the can thru both carbines



"Violence, naked force, has settled more issues in history than has any other factor.”
― Robert A. Heinlein, Starship Troopers

 
Posts: 6888 | Location: Texas! | Registered: October 07, 2006Reply With QuoteReport This Post
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Did some accuracy testing and re-chrono'd with the 12.5". Have 200rds on it now, velocity has settled. This thing is hauling ass. Not sure the midlength gas has anything to do with the velocity? Went up to 24.0/8208/77smk/2640 had slight ejector swipe. 23.7/2600 shoots very well. Will keep in mind it 45 degrees outside today. Things might change when hotter! Cycles great with the can, very soft shooting, port size is working out great. Throws brass in a nice pile at 3:30-4:00. Fun when things work out! Did try cycling w/o the can. One round in mag tried it three times. One the bolt locked back, other two did not eject the case. Hopefully next week shoot it at 4-500yds, see what magnification I need to spot misses/impacts on steel, go from there on a scope choice.

I ended up not using the Noveske NSR handgaurd. The .800 gas block just barely cleared the handgaurd. Put a little pressure on the handguard gas block will touch. Had a JP handgaurd laying around, plenty of room with it.
 
Posts: 2731 | Location: 9860 ft above sea level Colorado | Registered: December 31, 2008Reply With QuoteReport This Post
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As mentioned above had two barrels cut from the same blank. Game time decision went with a 11.5" for the second barrel, .063 gas port, carbine +1 gas system for 100% suppressed. Put the barrel on a older Sun Devil upper. Same procedure as other barrel, heated up the barrel extension.... nice tight fit. It ain't coming off w/o heat.

Shot 200rds though it yesterday, red dot sight, 25yds. Functioned great with all the loads. Slightly snappier compared to the 12.5", not bad though. Chrono'd the last 15rds. Interesting the difference in velocity between the 11.5" and 12.5", about 70fps. Once again barrels cut from the same blank, all components the same.

XBR8208/77SMK/CCI450/LC Brass

23.3-2490
23.5-2510
23.7-2530 No pressure, a bit over gassed


 
Posts: 2731 | Location: 9860 ft above sea level Colorado | Registered: December 31, 2008Reply With QuoteReport This Post
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Originally posted by offgrid:
Interesting the difference in velocity between the 11.5" and 12.5", about 70fps. Once again barrels cut from the same blank, all components the same.

I don't see that much change per inch of barrel for my longer barrels, but it does make sense that that MV change is greater as SBR lengths are compared. Good to hear that your barrels are working out nicely.

*****
So....which barrel/upper do you like better?

This message has been edited. Last edited by: fritz,
 
Posts: 6439 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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Originally posted by fritz:

So....which barrel/upper do you like better?


12.5", slightly smoother recoil pulse.

A friend gave me some MK262. Shot it through the 11.5". Stuff is scooting. No doubt these two barrels are on the fast side.

Swapped the grip to a Magpul K2+, puts my finger on the bang lever at a perfect 90.

 
Posts: 2731 | Location: 9860 ft above sea level Colorado | Registered: December 31, 2008Reply With QuoteReport This Post
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2526 fps for a 77 grain in an 11.5" barrel is moving. That SD is uber impressive.

MVs for my 14.5" LWRC, with factory ammo:
2470 fps -- Hornady 75 HPBT match
2533 fps -- Hornady 75 HPBT Black

MVs for my new 14.5" Wilson Combat, with factory ammo:
2477 fps -- Hornady 75 HPBT match
2613 fps -- Hornady 75 HPBT Black

FWIW, that 2613 MV with Hornady 75 Black is comparable to the MV from my 16" barrels.
 
Posts: 6439 | Location: Colorado | Registered: January 26, 2008Reply With QuoteReport This Post
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