Warning

 

Close

Confirm Action

Are you sure you wish to do this?

Confirm Cancel
Member Login
Site Notices
9/22/2017 12:11:25 AM
Posted: 9/29/2005 11:32:25 AM EDT
[Last Edit: 9/29/2005 11:34:01 AM EDT by glenn_r]
Back in 1993 I had a Colt HBAR turned into a service rifle, leaving me with a spare 20" Colt 1/7 barrel on hand. I finally decided to turn the spare barrel into a rifle, as all my other rifles were 11.5" to 16", so why not have a 20" too?

As I slowly acquired the funds, I purchased a RRA lower receiver from gunguyr, a CMT upper from dennysguns, and a RRA lower parts kit from Legal-Transfers. No hassles from any of the board sponsors. I traded a Colt bolt carrier for a Colt Delta free-float tube and bought a YHM gas block/front sight from Brownells. I finished it off with a spare Colt bolt carrier assembly, flash hider, and A2 buffer/stock assembly I already had on hand. Put on a Harris bipod and topped everything off with a Leupold Vari-XIII 1.5-5x on a SPR mount purchased from MSTN. (I still need a 40L-SP rear sight--have to figure out what dealer to farm that purchase to.) The WI hometown moderator BulletcatchR was kind enough to lend me the receiver block and I already had a wrench, so I was off to the races.


I took it out to the range for the first time today. 58 degrees, 42% humidity, sunny skies, breeze variable at 6-10mph. I started off with a function test of 20 rounds Federal AE 55gr. No problems, although the group eyeballed over 3moa!


Well, it has been a long time since I've been active in Service Rifle, so I figured I was pretty rusty shooting off a bench. I wasn't sure whether to hope I was shooting badly, or whether it was a rifle problem--either one was unattractive

I built this thinking it might be a decent small-caliber deer rifle (no flames from the anti-.223-for-deer crowd, it's legal here and I understand the limitations of the cartridge). So after adjusting the sights for the Fed 55-gr ammo, I put 5 rounds of Winchester 64-gr PowerPoints through it:



OK, down to 2moa, and I'm starting to remember some of the principles of shooting off a bench...like squeezing the trigger and follow-through . POI is about 1.75" off from the 55-gr FMJ load. I adjusted the sights, and got this:



1.5" 5-shot group, strung vertically, but right at 1.5" above point of aim. Nice windage, too! Amazing what a difference squeezing the trigger makes...

I decided to finish off the rest of the box of Winchester 64-gr ammo, and decided to test the QD "no loss of zero" feature of the SPR mount. So I took it off the rifle, then replaced it, followed by 7 rounds:



Another 1.5" group, centered and exactly where I wanted it...except for a called flier at 9 o'clock. I'm pretty happy with that.

Running the numbers, the Win 64gr (.234BC) @ ~2950fps 1.5" high @100yds w/sights 2.5" above bore gives me this trajectory:

YDS POI
0 -2.5
50 +.1
100 +1.5
150 +1.7
200 +.2
250 -3
300 -8.3

Since my hunting location doesn't have any possible shots over 175 yards, I think that should work well.

Finally, I finished off the test with all the remaining Federal Eagle ammo I had on hand, ~ 50 rounds, fired at 1/second, just to heat up the rifle. No function problems, and I got the HBAR smoking a little:



I still need to dump 200 rounds through it as fast as I can, to check the seating of the YHM gas block and give it a real wringing out, but so far I'm pleased.

Feedback? Comments?
Link Posted: 9/29/2005 11:44:10 AM EDT
Good report. Thank you.

I'm kinda doing the same thing in that I'm just now starting to piece things together. Glad to see the results of hard work and time spent.
Link Posted: 9/29/2005 12:41:44 PM EDT
Nice Build, and good range report.
Link Posted: 9/29/2005 1:03:10 PM EDT
Link Posted: 9/29/2005 1:24:15 PM EDT
Neato!

Great looking/shooting build.

Danny
Link Posted: 9/29/2005 7:38:16 PM EDT
Good job, Glenn. No flames here on 223. My daughter took her first buck at 14 years old with the AR15 that I had at the Carbine 1/2 class. Just had to put a pic in local paper with her and deer and AR15 with 20 round clip. That's my baby!!
Cheers,
Dave
P.S. My new CMMG M2 SBR w/10.3 barrel has shipped and should show up Monday
Will be parking it next to the Uzi
Link Posted: 9/29/2005 7:46:18 PM EDT
Looks good and nice documentation
Link Posted: 9/30/2005 4:01:35 AM EDT
nice looking build
Link Posted: 9/30/2005 4:54:14 AM EDT

Originally Posted By usagold:
nice looking build



+1
Top Top