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30mm to 1" scope adaptor - I gained weight for this?

Posted: July 17th, 2018, 6:00 pm
by Harrier
Everything is a long story with me ... so here is the summary version...

I bought a 30mm AR-PEPR style mount (with 1" reducer inserts) - Weaver brand but it turned out to be a one-screw base mount so I didn't think it would hold a long scope very well. Had it been turned around in the package so I could see the mount setup I wouldn't have bought it. Oh well, it can be used for short scopes so i kept it.

next I needed to add some $ to a Midway order to get free shipping (yeah, right- ok a reduced order price), so I added a 2 screw Weaver PEPR 30mm style mount. I noticed it didn't include a 1" reducer but hey, I already had a Weaver with one... what could go wrong?

I need that reducer because I have yet to cough up the bucks for a new Vortex, so I am trying to get by with a couple old scopes for the time being. I have a Burris Signature 8-32 I would like to use and a Tasco 6-24 if I have to.

When the new mount arrived I quickly found out the other weaver reducer would not fit the new mount. It has a 'lip' on both sides to lock it in place and the old one-screw mount is about .625" in width whereas the 2-screw mount is .75" wide. Weaver doesn't seem to make or offer a set of 30mm-1" reducers... Why do designers make these things incompatible? I fired off a letter to Weaver CS and have yet to hear a reply (over a week). Next time I will buy a different brand- they don't seem to need my money...

So what to do? I looked at the various on-line offering but they were either 5/8" or 1" wide or didn't say. Nothing 3/4" and it would cost me an additional $8-$15 plus S&H.
Looks like I would have to either cut one down or make do with a too short shim... or make my own.

i decided to see if I could make one from crap i have laying around (actually crap is my wife's term- it is really good sh*t that is useful for something- I just gotta figure out what).
Looking at my bench, I know there is something I can use
1 Find Material.jpg
I Found an old web belt that was too short for my new physique- (substituting ice cream for beer is not a viable weight loss solution).

A test fit showed it is flexible enough to wrap around a 1" scope tube yet stiff enough to hold the scope in place without movement- and just the right thickness to take up the gap between 30mm and 1".
2 Testfit.jpg
3 Tryscope.jpg
Next I cut it to width and fitted the scope to the rings.
4 Cut width.jpg
5 Mount scope.jpg
Then put the mount on the gun
6 Setup on Gun.jpg
Here is the setup, ready to go sight it in- (some of you may recognize this SPR in its new configuration)...
7 Final Look.jpg
Range test to follow.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 17th, 2018, 6:16 pm
by redj
I believe it will work but I also believe if it ever gets wet it will be a problem by rusting both the mount and scope.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 17th, 2018, 6:26 pm
by Harrier
rain here in Arizona? naw, your kidding me right?....

This is a temporary solution until i get a 30mm scope or a better set of reducers- besides, i don't think I will be shoot'in in the rain any time soon... well, wait a moment... it is monsoon season and I did live in Oregon for a while, so it is very possible...
good point redj, thanks for the heads up, the mount is aluminum and the tube I'm not sure but has a good heavy finish but I'll try to keep it dry.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 17th, 2018, 6:53 pm
by redj
I didn't think about it being aluminum. I have seen rust on mounts and scopes before , but they were quite a bit older than what you have.
Another thought about it getting wet. Would it swell and change the point of impact ?

All in all It is a good idea if you are in a pinch.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 17th, 2018, 7:16 pm
by Harrier
I'm not sure if it would change POI when wet or if it is compressed enough already, I torqued it to 30 inch lbs.
Maybe I should sight it in then throw a bucket of water on it?

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 18th, 2018, 5:09 pm
by shooter444
Harrier, been there, remove the ridge/lip on the reducer with a fine rat tail file.

Worked for me.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 18th, 2018, 5:22 pm
by Ballistic Therapy
shooter444 wrote: July 18th, 2018, 5:09 pm Harrier, been there, remove the ridge/lip on the reducer with a fine rat tail file.

Worked for me.
That's what I would do.
File it down and do the finish work with sandpaper.
If it's aluminum it will work just like soft wood.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 20th, 2018, 5:39 pm
by Harrier
I thought of doing that, only minor issue is the scope rings are .75" wide and the adapter i have seen either don't say their width or are .625" and 1" wide. I one case it would be 1/8" short and the other I would have to cut it down.

So far this is working just fine and will probably stay in place until I replace the scope. I did 135 rounds on it the other day and nothing moved.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 21st, 2018, 12:08 pm
by shooter444
Harrier, I don't think your scope will have a clue if the spacer is more narrow, or wider, than the rings that hold them. If I had to make the choice I would go with the spacers that are wider than the rings. Do as you think best, but, spacers made from a collapsible organic material will have a propensity to retain moisture, and will more than likely have to be checked/maintained regularly, imo.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: August 4th, 2018, 6:29 pm
by 792mauser
I tried one of those single bolt setups. It won't stay tight on my a4 clone.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: June 17th, 2019, 10:53 am
by DillyCleo
30mm to 1" delrin adapter are cheap - don't do that with the webbing you'll regret it.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: June 18th, 2019, 8:53 am
by Delfuego
Buy some 1" rings and sell the 30mm and be done with it.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 8th, 2019, 1:38 pm
by azrik
Great fix, I woulda used beer can material wrapped around it but that's cuz that's what I have laying around.
I fit an Ultimak rail on an AK once with feeler gauges.

Re: 30mm to 1" scope adaptor - I gained weight for this?

Posted: July 9th, 2019, 8:33 am
by Harrier
Delrin spacers may be cheap but I'm cheaper...

I finally replaced the scope with a 30mm Vortex PST- Now the rings fit without adapters, as they should.
The web belt worked for a few months without any issues but then i didn't pee on it either.
Thanks for all the interest and comments, I wouldn't hesitate to do it again in a pinch.