minimum scope clearance between barrel

StevieK

StevieK

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I mounted a 42mm objective scope onto my browning x-bolt. The rings are low so I literally have the scope sitting so close to the barrel that there is a fraction of light can be seen underneath it from the right angle. It definitely ISN'T touching now. Just wondering if mounting this close can create any problems? I took the gun to the range and it shoots like a shotgun, I'm getting like 6" groups. The gun is brand new, scope bases and rings are all loctited. So i'm wondering if the scope position could be playing into this. Is this kind of accuracy normal when breaking in a barrel? I've never shot a brand new gun. The gun is in 223 btw, so heavy recoil causing things to move isn't a huge concern either
 
That rifle should do much better than that. But, there's a number of things that might play into this. What scope & bases are they? What range are you trying to zero at? Photo maybe?
 
If it isn't touching, you have enough clearance. I personally am not a fan of Loctite on rings but some do use it.
 
its not the scope or the rifle, or even the mounts for that matter.........

stop shooting Winchester white box ammo and your groups will shrink 5 and a half inches right off the bat
 
yodave said:
its not the scope or the rifle, or even the mounts for that matter.........

stop shooting Winchester white box ammo and your groups will shrink 5 and a half inches right off the bat
Click to expand...


Haha I actually was using the winchester powerpoints...I usually stick to federal blue box when I sight in with cheap ammo but the gun shop I was at didn't stock federal. I don't think the ammo could account for that kind of shotgun scattering?
 
in my opinion you need to be able to fit as business card under it.

Check out YT for some Slow motion shots , you will see there is movement in scopes that could make it touch. (well maybe not on a little 223)
 
Does your scope allow you to correct for parralax? Is your cheek weld the same each time and having a clear sight picture in your scope ie no shadows etc. I've got about 1cm of space between my objective bell and the rifle. What scope is it? Maybe it's not holding zero? While not absolutely necessary (constant pressure against the barrel is) but is the barrel free floated or was it built not having a free floated?

My rifle was about 2-2 1/2" MOA out of the box until I bedded it, free floated the barrel and started using handloads. 6" groups sounds like a LOT, even with cheap factory loads.
 
As long as the bell doesn't touch the barrel there should be no problems. I have a couple that are very tight as well. Have you tried different bullet weights? Maybe your rate of twist doesnt agree with what you're feeding it. The only X bolt I've shot was in 300 WSM, but it would put three shots at right around an inch off a bench. If your scope mounts/rings are all torqued properly check to see the screws at the action are tightened properly, barrel is free floating, etc...
 
scope is a 6x42 monarch. The last gun it was on shot just over 1" groups, and that was on a lightweight kimber so I think the scope is just fine. sighting distance is 100 yds
 
try the business card first for clearance, double check your action screws, then buy a better box of ammo..........no wait I have a idea.....do those 3 things in reverse.....try better ammo first, then work backwards.....pfft winchester
 
yodave said:
its not the scope or the rifle, or even the mounts for that matter.........

stop shooting Winchester white box ammo and your groups will shrink 5 and a half inches right off the bat
Click to expand...

Oddly enough I have a Savage/Stevens that just loves that crap. The 55 gr hollow points shoot like a dream. Only trouble is the tip design digs in and jams every couple rounds so I'm hand loading ballistic tips instead.
 
I got 12 inch groups in 3 rifles with it just trying to unload it for the brass...........then I decided maybe being cheap wasn't working for me and I ended up financing some lapua brass
 
I like to keep my objectives very close to the barrel without touching. I'm inclined to suspect your ammo as well. Winchester ammo has gone right down the crapper in recent years.Like someone else mentioned, your bullets might be too light for your twist rate. Try different ammo,maybe 62 gr or so.
 
StevieK said:
The x-bolt has a 1-12" rate of twist so I figured I'd be safe with 55 gr ammo, I thought 62 would be on the heavy side
Click to expand...

It depends on the shape of the 55 grain bullet.
If it is long and pointed, it may very well not be stabilizing.
No ammo off the shelf is that bad, if everything else is right. If you are going to change ammo, get a lighter, shorter bullet.
 
I've got 2 boxes of 40gr V-max bullets that I'm hoping to load for it, just wanted to use some cheap factory stuff to zero the scope before I loaded up the brass. But I can't start testing reloads if the gun is shooting 6" groups to start
 
buy a box of good factory ammo and rule out your Winchester ammo, then reload and shoot the Vmax's
 
Try a shim under the barrel at the forend tip, putting a little up pressure on your barrel (about 4-5 lbs), you may find this helps significantly. I'm guessing that 80% of my sporting weight barreled rifles have forend shims and shoot the best this way.
Nothing wrong with your scope mounting, I try to get all my scopes within .030" obj bell-barrel, or less............
Ignore those who say this kind or bullet spraying is due to too fast a twist, that is absolute bunk. Many studies have proven that it is almost impossible to over-stabilize a bullet and any noticeable decrease in accuracy would only be discernible at the benchrest level. I have experienced what happens when you over spin a bullet.........it turns into a gray mist at about 30 mtrs from the muzzle, but the load previous shot 3/4" groups.
I can give no opinion on the X-bolt as I've never owned or even fired one, others seem to be getting acceptable accuracy, or it would be all over the internet if not. The same goes with your scope as I use exclusively Leupold or Zeiss............
 
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