Home Forums Hunting & Shooting Ask The Gunwriters Rem semi-autos vs scopes

Buddy of mine has a Rem 742 in 243 - SEEMS to have eaten 2 (cheaper) scopes in a short period of time. We get decent groups, devolving to pi$$ poor groups in less than 20 shots!
Does the vibration (for lack of a better term) destroy these bottom dollar scopes, or do we need to be looking for a different problem?
Groups start @ 3" @ 100 yds, & rapidly deteriorate to 16-20" groups @ 100 yds (less than 10 rounds fired on each scope)
Factory ammo used to this point.

Mark

Your buddy should invest some money in good optics he will never be sorry.I dont shoot a Remmy autoloader but do know several guys that do without scope problems.It could be other problems as well scope mounts or putting to much torque on the rings.

Not sure, but wouldn't the bolt banging into the rear of the receiver/bolt stop give some nasty counter vibes? As said above invest in a good scope. Most hunters in my family had Remington 742/7400/4 rifles back in the day and none really had scope problems. They wanted fast follow up shots at running deer that were ahead of the dogs. That wasn't legal, but they did it anyhow.

I have had several 12ga Remington autos with the receiver drilled and tapped before the cantilever mounts came around.The bolt hammering back from a 12ga slug never killed a scope for me FWIW.

After twenty rounds, that barrel is plenty hot, more like a noodle than a decent pipe. I'd suspect that barrel heat is causing the group sizes to expand.
That was always the case with my cousin's .243 742.
You didn't state that there was any cooling period for the barrel, 742s heat up BAD, and quick. Let it cool off, it ain't an M14, and accuracy WILL go to Hell quick with one of those POS.

Three shot group let it cool to ambient temperature then shoot another group.

Fouling?

Exactly. Semi automatics have a negative recoil impulse just like a spring piston air rifle. Cheap scopes are not designed In a way that anchors their internal bits from reverse recoil.
A better scope should last longer, but it is not until you get to really high end scopes like Nightforce or lower end air rifle specific scopes where you can essentially forget about a scope failing.

Don't know about all that speculation, but...

My 7400 in 35 Whelen digested hundreds of max loads, from 200s to 250s, and NEVER was there a problem with accuracy or a failing scope. I was shooting 200s at 2800+fps, 225s at 2700+ fps and 250s at 2500+ fps. And, that was literally hundreds without a hitch or problem of any kind. Wish I still had it, but it tended to be heavier than I wanted for my kind of hunting.

Bob

www.bigbores.ca

Another factor might be scope mounting. If he mounted the scopes himself, or even had the average sporting goods store mount it, the rings might have been WAY too tight. Most scopes won't work very well for very long if crunched by too-tight rings, no matter how much the scopes cost.

And now that I'm out of the gun biz, ALL stores are just average....