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Dussalater · Member

I bought a winchester 1000sb and used that scope until it messed up. So i bought another 4x32 scope. will the same mounts work?

oddtodd · Silver Status Member

It depends on the body of the scope. You'll have to measure the body of the old scope and the body of the new scope to be sure. Using an educated guess, the probably should. I wouldn't try it till I measured both though.

Alstone · Moderator & Site Supporter

Scope mounts usally come in two sizes 25mm/1" or 30mm, so you will soon see if it fits or not.

Al

super6 · Member

Yes.

Ray

oskar · New Member

I recently bought a new BAM B40 .22cal underlever rifle with a Nikko Stirling 4X32AO scope. I have had trouble zeroing the scope and just today I found that the rails on the B40 are 11mm and the scope dovetail is 3/8". Will the NS scope work properly on the 11mm scope mount rails?

fritz · Silver Status Member

11mm = 3/8" for airgunners.

25mm = 1"

.177" = 4.5mm

.22" = 5.5mm

.20" = 5.0mm

.25" = 6.35mm

oskar · New Member

[quote="fritz"]11mm = 3/8" for airgunners.
Thanks for the reply but what do you mean "for airgunners"?

3/8" is 9.525mm which puts the scope about .75mm offset to the centreline of the bore. I recon that distance could be significant at 30M or so if you have it zeroed for 10M, 15M or even 20M.
You are sighting diagonally if the scope is to the side of the bore.
Or does it not matter at 30M?

kanyon · Silver Status Member

Slavia · Moderator

With a 0.75mm offset and the gun zeroed at 10m, it will shoot 0.75mm to the other side at 20m, twice that at 30m, 3X at 40m (2.25mm), etc. Zeroing at other ranges will make the effect less pronounced.

If it were me, I don't think I would worry about 2.25mm of error at 40 yards - wind and my own lousy shooting would put me centimeters off target.

I suppose it all depends on how accurate your gun is and what you're shooting at.

fritz · Silver Status Member

I don't think you're right about it being off center, but IF it is... I see no difference.

My Diana 34 is dead on in the windage department if I sight it at 10 yards and shoot 35 yards, only elevation changes. If I use mildots and go out to 50 yards with a ~22yard sight in, I'm only 2 dots down on 10x. Infact, I was shooting dead center, but 2 dots low at 50 yards. The 9 eggs I had up on the target line (eggs blow up nice, try them sometime) were hit directly in the center, either up or down, no left/right variations.

I also think most 11mm/3/8 mounts are smaller to account for that. Even if not, as Slavia said, the difference is miniscule. Cool

oddtodd · Silver Status Member

I have an offset on one of my rifles like that, and it doesn't make a difference because I'm not accurate enough for the offset to matter. Matter of fact, I'm more accurate with my pistol than a rifle. Never could figure that one out.

oskar · New Member

Yeah. Thanks guys
I just did the same diagram on Autocad and got the same result (2.25mm @ 40M) when zeroed at 10M.
I zeroed mine at 20M and that makes a .25mm difference at 40M as you said
Gee .. it would be nice to be that accurate

fritz · Silver Status Member

If you are hunting, zero at like 25 for medium to low powered guns. High powered may need 30-50 yards.