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scope slipping, SWFA 10x42

lowkeyy

Private
Minuteman
Jun 3, 2014
3
0
So I am new to long range shooting and mounted an SWFA SS 10x42 on top of my S&W MP10. After shooting ~50 rounds, we discovered that the scope had slid forward until the parallax adjustment ring was touching the scope ring. Interestingly enough I was still shooting 2 MOA at 450 yards and relatively on target (I am a newbie so not too bad I guess). The configuration of the scope was so that the scope could have moved at max 1/2" before it touched the ring.

Basically has anyone heard of serious damage to a scope by a scope sliding? Should the SWFA with its reputation be expected to still perform?

I will be able to shoot again in a week or two to confirm. I have also since put this scope on a SAVAGE 11 and will begin the break-in for that gun (and I used a torque wrench this time).
 
You can throw that thing down and stomp on it and it will still be ok. It's fine, go shoot and enjoy it.
 
Sounds like a problem with how you installed it in the rings. Make sure any oil inside the rings is cleaned out and the bolts torqued to manufacturers spec.
 
I mounted the same scope on my Savage 10. I had very little clearance between the parallax adjustment and the rear of my scope base. After about twenty rounds I realized I couldn't move adjustment ring. Took the scope off and noticed two gouges, each 1mm deep and 3mm long. The parallax adjustment still works like new.
 
Clean and dry the rings. Apply some rosin/resin/rozzum on the inner surface of the rings. Tighten as usual. Keeps things in place.

The reason for the "rosin/resin/rozzum" is because one of my very early posts had to do with using resin on scope rings. Boy, what a shitstorm that started. Call it what you may, it makes things stay in place.
 
Thanks for the replies guys. I am sure there is much to be said about getting a scope to stay in place. I was hoping that just 25-30 ft. lbs. of torque would do (mfg says 20 lbs). Can this not be enough?
 
I seriously hope you mean inch pounds. What rings are you using?

Yes, I definitely mean inch pounds. I am using Burris Extreme Tactical rings. I am assuming these do not need any adhesives, but I do not have much experience either way. I alternated each screw from opposite end and sides like a car tire on all of them, and did three "laps", increasing the torque wrench 10 lbs each time.
 
scope slipping, SWFA 10x42

Get good rings and your problem will go away.
 
Had a problem like that once----quality rings--quality scope----carefully re-mounted---slipped again (and yes, you can damage a scope by allowing it to be pounded against the rings). Had the idea of applying some Permatex silicone engine gasket sealer; just a 1/8" rounded dot to top and bottom of the rings----scope has never slipped since-----and the silicone sealer will peel off the scope when removed for other reasons. (Leupold rings on a Leupold 6.5 X 25 MK 3 with 1 inch tube).
Good Luck

IF---a monster scope is mounted on a rifle with serious recoil-----2 rings are not always sufficient. Once used a McMillan 50 with 3 Warne rings to hold a 8.5 X 30---56 Ob scope.
 
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Blue loctite on the scope ring cap bolts, torque them down properly and to spec, and those things will never come loose again (which is the only reason your scope would slip).
 
Blue loctite on the scope ring cap bolts, torque them down properly and to spec, and those things will never come loose again (which is the only reason your scope would slip).

What he said, but while tightening the turrets push down on them, then insert the little hex screws and tighten. If not, the air trapped inside keeps them from wanting to go all the way down.
 
The SWFA is built like a tank. I agree that some quality rings should alleviate any problem that you are having.
 
5 pieces of electrical tape - 1 piece of tape each trimmed to put on the inside of the top cap, 1 piece of tape trimmed to put on the inside of the bottom of the ring. 1 piece stuck to the scope, bumped up against the ring once mounted as a "witness" - if the tape on the scope starts getting ripples, or a gap is seen between the ring and tape, i know it's slipping in either direction.

clear nail polish or loctite for the screws.
 
scope slipping, SWFA 10x42

I run the Burris XTR's. I have lapped both sets that I bought and found that one ring would have maybe 20% contact and the other 40% contact on the bottom rings. I lap the top and bottom rings together until I get at least 90% contact and then install the scope and torque everything with a wheeler Fat wrench. That scope ain't going nowhere. They aren't expensive rings, but with a touch of elbow grease they turn into real nice rings.

Edit: For reference, rings were mounted on a weaver aluminum 0 MOA base on a Stephens 200 .308
 
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