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View Full Version : Trouble in Paradise - Flex?


KnowFear
01-14-2012, 4:33 PM
Pic shows sequence of events, all at 25 yds, Marlin 60 - 1) is zeroing in, 2) and 3) are verification and a small tweek.

4) My first attempt at using the sling - using hasty sling, felt kinda tight at maybe 5 lbs tension or so - shooting down and left by inches!^@%%??? WTF???

Thought the scope may have had a brain fart or something, so shot I a quick group 5) back on the bench.

Sling is attached to the mag tube with Uncle Mike's Marlin 60 tube sling stud thingy and swivel.

Am I really bending the barrel and other parts so much to shoot off by inches?



http://i154.photobucket.com/albums/s257/KnowFear1111/SCAN0140_1.jpg

G-forceJunkie
01-14-2012, 5:25 PM
Very likley. I would attach the sling to only the stock. Install another stud if you have to.

PurplePeople
01-14-2012, 8:09 PM
It's possible. At one point I tried using the carry sling on my Kel-tec 16 as a hasty sling in sitting. The forward sling attachment is pinned right through the gas block on the K-T, which puts the load on the barrel and gas tube. I got a POI shift of about 6 inches down right at 50 yards (I shoot lefty), which is the MOA equivalent of what happened to you at 25 yards.

A bit of math: 3 inches offset at 24 yards is 12 minutes of angle (MOA). An MOA is 1" / 100 yard (300 feet). So one MOA of offset at the end of your barrel - let's say 18" length - is .005 inches. 12 of those is .06 inches - so if you think you could have deflected the barrel / tube that far with the tension you put on it... could happen.

The way to check is to try it at the range again, starting in sitting without using the sling, then adding the sling and putting on progressively more tension, to see what happens. If it's all shifted, then it's your sight alignment/picture; if you get a progressive shift in POI, it's the sling.

KnowFear
01-16-2012, 12:26 PM
No more sling attachment on the mag tube of the Marli 60. Bad Uncle Mike.

Clearanced out the Boyds Stock some more with the round file such that barrel and mag tube are not in contact with the stock, and attached the slings to the 2 studs that Boyds had pre-installed in the stock. Problem solved - no more deflection under sling tension.

Had to try out my best guess for the 4 positions and sling use. Shot a 187 on the AQT - lots of room for improvement!

I swear that prone position with loop sling is more stable than my crummy plastic patio table and the bipod.

Don't worry instructors, I won't be shooting the positions any more for fear of acquiring bad habits or form, but will be doing a lot more stretching to loosen up my rickety old carcass.

PurplePeople
01-17-2012, 6:11 PM
Don't worry instructors, I won't be shooting the positions any more for fear of acquiring bad habits or form, but will be doing a lot more stretching to loosen up my rickety old carcass.

+1 on the stretching. It really can help: After a serious accident put me on a walker/crutches for four months back in 2008, I couldn't even get into sitting position due to stiffened muscles. Several months of stretching made it possible (not comfortable) again.

You want to hit the groin muscles for sitting, and neck and the long back muscles for all positions. If you've got some time for strength work, again the long back muscles for all positions, and lats, biceps and triceps for standing.