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Gregas
04-04-2006, 10:13 PM
Took my fixed mag rifle out to the range on Saturday for accuracy testing w/ handloads. This is configured as an A2 for Service Rifle competition. It's got a White Oak Armament upper with a 1:7 Wilson match barrel, pinned sights, Geissle trigger in a Lauer Lower.

I'd been out twice before but have never gotten great results. Reading John Feamster's Book "Black Magic", I learned that the carry handle is a sucky place to mount a scope (although there are no better options for the A2). Following his advice, I epoxy bedded the scope mount to the carry handle. After a bit of a scare (use plenty of release agent!) it now fits great.

Voila, instant group improvement! It now shoots *always* less than an inch at 100 yds (5 shots) averaging about 0.65" with a smallest group of 0.37". This is on a breezy day in the hand of someone with poor bench technique (me), so I'm pretty happy.

I'm shooting Sierra Matchking 52gn and 69gn over AA2230C and CCI41 primers. I'm really glad the AA2230C is working out, since I have enough for the next couple of decades (it was on super sale $54/8lbs and one hazmat fee covers up to four jugs!). I'm hopping to get the average close to 0.5" with a little fine tuning of the load.

Enjoy your new rifles! I know that I am.

Greg

C.G.
04-04-2006, 11:00 PM
This thread is useless without pics!!!:(

Gregas
04-04-2006, 11:49 PM
This thread is useless without pics!!!:(
Sorry I dont have any range pics...

Here is the rifle and the results...(that group actually has 5 shots..two through the same hole)

775

776

C.G.
04-04-2006, 11:55 PM
Much better!:)

OptionX3
04-05-2006, 12:22 AM
What kind of carry handle mount and epoxy did you use? can you elaborate more on the process?

Gregas
04-05-2006, 10:59 AM
I can't remember exactly what brand carry hand mount I have, it was inexpensive. I don't think it matters much because it probably won't fit tightly enough, no matter what brand you get. If there is any play at all recoil causes it to rotate around the single screw, chaning your point of aim.

For epoxy, I used Acraglass Gel bedding compound, available from Brownell's this has a very thick consistancy and is easy to work with. I only used a tiny bit. I have enough left over to bed several wooden stocks

Procedure:

1) Apply multiple thin coats of release agent (comes w/ kit) using a q-tip. Put it on evenly and allow each coat to dry (a couple of minutes). Directions say three coats. You can use a bit more, but they should be thin, even coats. Make sure that you have full coverage of the channel, the inside of the hole and the area just outside the channel. Put some on the threads of the scope mount screw, but nowhere else on the scope mount (you want it to stick).

2) Mix bedding compound according to directions and smear a thin layer over the bottom of the mount. Get complete coverage, but leave it thin, you'll have less squeeze out mess.

3) Put the scope mount on the carry handle and tighten the screw gently. Do not make it tight. You want a thin coating to remain, so don't squeeze it all out. Carefully clean up any squeeze out. Let it set for 24 hours (or according to directions)

4) This is the *****. You now need to break it free. Hopefully you put on enough release agent. After several unsuccessful methods, I put a stout allen key into the tube in the mount (it is a see through mount) and (after loosening the screw) and pushed it hard side-to-side, up-and-down until it broke free. It was a pain and gave me a scare, but it did come out clean.

Now, the mount pretty much snaps into place with no play. Just for good luck, I also tighten the knurled screw with pliers. That sucker does not move at all now. Finally, I can see the accuracy of the gun.

C.G.
04-05-2006, 11:35 AM
Instead of release agent one can also use thin plastic sheeting as in Safeway plastic shopping bags. Any remnants can be burned off with a heat gun.

Gregas
04-05-2006, 12:25 PM
Instead of release agent one can also use thin plastic sheeting as in Safeway plastic shopping bags. Any remnants can be burned off with a heat gun.

My only concern is that you want the layer of release agent (or bag) to be really, really thin to get as close a fit as possible. The stuff that came with the kit worked fine, you just have to make sure to apply it correctly.

xrMike
04-05-2006, 12:34 PM
What kind of scope and mount are you using? Maybe a pic with the scope on the rifle, por favor? Also, how's the eye relief/comfort/usability with the scope sitting way up there on the carry handle?

I have a WOA upper coming too. I'd like to eventually mount a scope the way you're doing it, which gives you the option to take it off for Service Rifle matches.

Also, anyone know what is considered the best/most secure mount for this application?

Gregas
04-05-2006, 1:01 PM
What kind of scope and mount are you using? Maybe a pic with the scope on the rifle, por favor? Also, how's the eye relief/comfort/usability with the scope sitting way up there on the carry handle?
I'm using a Leupold VX-III 40mm 6-20 (If I recall correctly). I don't know who makes the carry handle mount. The height is just fine. There really is not enough eye relief, ie. I'd rather have the scope further forward. Since I only use it when accuracy testing handload, I just deal with it. I'll post pics when I get the chance.

Also, anyone know what is considered the best/most secure mount for this application?
I don't think that there are any better options for the A2. I looked arround and asked over at AFCOM. If you really want a scoped rifle, an A4 is far superior. However, if you want to shoot Service Rifle, like you and me, and only use the scope occasionally, this is good enough (after you bed it).

I was going nuts until I read about bedding the mount in "Black Magic". Since the mount is only held on with one only screw, to get good accuracy with the scope you really need a perfect fit in the carry handle channel.

NRAhighpowershooter
04-05-2006, 2:12 PM
My 'off list' lower won me Expert Class in Calif's State Service Rifle Championships :D :cool:

Gregas
04-05-2006, 4:29 PM
My 'off list' lower won me Expert Class in Calif's State Service Rifle Championships :D :cool:

Nice. I'm going to use mine in a club match for the first time soon. I'm still getting used to the difference (from the M1) in handling/shooting positions.