I've Almost Done It IV: A New HELP!


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Joshua M. Smith
July 17, 2010, 11:18 PM
Hello,

Yes, I skipped the "I've Almost Done It II" & III because the pun was just too good :D

In my ongoing quest to get sub-MOA 100yd groups from bulk ammo, I sort by weight and modify using D Rock's tool. I've recently switched to American Eagle 38gn HP. The bullet weight and powder charge are very consistent, but the cases are not - they seem to vary largely on the amount of priming compound, and some are therefore louder than others.

I come sooo close to sub-MOA 5 shot groups many times, and have broken it numerous occasions if I throw out a flier or two, but there always seems to be one or two that prevent the sub-MOA five shot group.

Here are two of the best groups I managed tonight, out of a total of three groups:

http://i19.photobucket.com/albums/b191/WabashShootist/Guns/hollowpointer/6615a37e.jpg

http://i19.photobucket.com/albums/b191/WabashShootist/Guns/hollowpointer/6cb3f5c5.jpg

As you can see, three are sub-MOA (with one three shot group being almost 1/2 MOA at 100yds!). However, I have vertical stringing.

I need to see if I can get some help with that.

My front rest was the rifle's bipod, and the rear rest was a squeeze sock.

I shot prone, sniper style (vs the one leg bent position I'd been taught).

I know I had a little vertical movement, but this much?

The wind was dead calm. I didn't have to adjust windage at all.

Do you suppose I'm at the mechanical limits of the gun, my own limits, the limits of the ammo due to the inconsistency of the primer charges and the whole sonic barrier thing, or all or none of the above?

My 'scope is a Mueller 4.5-14x APV. The rifle is a Savage MkII BTVS that I pillar bedded. The barrel is definitely free floating.

Torque on the action screws are 55in-lb front (this one has been modified to take a main bolt) and the rear, being stock, takes about 25in-lb or so.

Is there something I should be doing that I am not? Or am I just pressing the limits too much?

What do you all think?

Thanks,

Josh

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WNTFW
July 18, 2010, 12:56 AM
In the 2 pics most of the problem is vertical. My thoughts:

I would question the ammo - possibly some deviation there. Test shooting at a slightly less distance and see if there are good groups and blow out suddenly at a certain range. Perhaps 5-15 yds may be enough to make a big difference.

Try shooting with your lungs empty not half full - if that is what you are doing. Getting 1 leg up or rolling to one side can help. You can work out a lot of that with out firing and just being in position behind the rifle.

Load the bipod the same every time.

How is your parralex and cheek weld? Do you use NPA?

Make sure your target is rock solid as a moving target won't help.

Big_E
July 18, 2010, 03:12 AM
I have had an experience with American Eagle ammo where 2 shots would be touching and a third would be high and to the left. I thought it was shooter error (slightly) but having a few shooters yielded the same results. So I believe there are inconsistencies in the ammo.

Now I am just waiting for I've Almost Done It VI: Return of the Jennings. :D
I'll stop with the Star Wars now... Darth VEPR... okay done now.

halfded
July 18, 2010, 10:34 AM
Ditch the bipod and sock for a proper bag set. I use the 2 bag set from Caldwell. Then learn how to set them up properly. That should help eliminate most of the vertical stringing. I also like to shoot my gun "free recoil". Basically means having no contact with the gun when firing except a light "pinch" on the trigger and the back of the grip. Cheek to stock contact is kept to an absolute minimum without losing consistency. WHen the gun fires allow it to slide back under it's own recoil. After each shot you should have to push the gun forward a small amount to get back on target.

Also, try using the smallest target you can still see. I use 1 inch file folder stickers (colored sticky dots) from walmart. At 100 yards and 9x magnification, my crosshair all but covers the dot allowing a more precise aiming point. Another option would be to use the targets that have vertical and horizontal lines on them. Line your crosshair up on the corner of a square; doesn't get more precise than that. A bingo marker on some blank white paper would work too and much cheaper.

Adjust your scope to hit about 1/2 inch or so above or below where you're aiming to preserve your POA. Shooting at an ever-widening bullet hole doesn't help things much. Besides, it's fun explaining to people that you "missed on purpose"!

Try Federal Lightning (used to be Champion) in the red box. $1.47 from wal mart; best cheap ammo I've found yet.

Here's some informal groups at 100 yards on steel. Those are 3 inch targets.
http://i625.photobucket.com/albums/tt332/halfdedsphoto/001-11.jpg

Shooting the same gun BTW, only a different scope and mine's the blued finish. Only mods were to lighten the trigger by about half. Here's what I got out of it the first time I tried Wolf MT:
http://i625.photobucket.com/albums/tt332/halfdedsphoto/100yardgroup22flyer.jpg

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