Baker Airguns 39x scope mount failure to remedy the usual 39x scope mount issues

[jakeadks]

Hi folks
I'd categorize the problems with the various available aftermarket scope mounts for the benjamin 39x as either (1) putting stress on the soldering that holds the barrel/breech to the pump/valve etc tube AND/OR (2) lacking lateral stability due to only coming in contact with the barrel/breech and at most one side or the other of the pump/valve tube, thereby allowing the mount to NOT be perpendicular to all-important vertical axis of the rifle. I know that Baker Airguns has discussed this on youtube, and their mount is supposed to avoid these issues by transferring the lateral stress of a mounted optic to the pump/valve tube. I received my BA mount today, mounted it on my 392, and unfortunately realized that it fails on both counts. The idea is sound; the mount is designed to fit around the breech and rest against the pump/valve tube on BOTH sides of the breech. However, it does not achieve this. It is not 'tall' enough to achieve contact with the pump/valve tube on both sides. When the screws on top of the BA mount are tightened, it will pull the mount UP against the breech, and, if aligned properly with the vertical axis of the rifle, will NOT be in contact with the pump/valve tube at all. Because of this, all the stress of having an optic mounted on the rifle will still be focused on the soldered joint between the breech and the valve/pump tube.

I expect that the mount was designed for the older 39x's (sheridan ETC), and that when paired with one of them these issues wouldn't arise. However, I have a new model 392. As I see it, the options remaining to me are to either accept that the soldered joint will eventually fail, and use the mount as-is, or to create that contact with the valve/pump tube through some additive process (JB weld or shims). Has anyone else had this issue? Solutions? I don't believe that my mount is a lemon as the fit and finish is as expected. This mount still has more potential for success than the god-awful Air Venturi mount that it is replacing.


*edit: I think that I did post this in the wrong gate originally, this is a duplicate post, now in the proper gate.
(fixed) 

[Habanero69er]

Jake, I have the Mac-1 IA mount on my pumpers. It does not promote barrel separation, is self centering & can be scout mounted as well as breech mounted. IMO, it's the best mount out there.

http://www.mac1airgunshop.com/product-p/bjshia.htm

[jakeadks]

Habanero, thank you for the reply
I considered the MAC1 mount before purchasing the BA, but it appears in photos to only attach to the barrel. Is this the case? If so, how is it possible that it does not promote barrel separation?

[RBQChicken]

I have a MAC1, and it's nice, but how is it self centering? I don't see that.

[Habanero69er]

Jake, it does only clamp onto the barrel. So it doesn’t put pressure on solder joint or air tube causing barrel separation.

Randy, I should have said the IA centers the barrel in the mount’s clamp. Obviously, you still have to adjust it for cant.

[RBQChicken]

That's what I was thinking of, cant.  Is there a way to make sure you get it vertical, other than just eyeballing it?

[Habanero69er]

I use two bubble levels. One on top of the mount and one on the inside of the trigger guard. To my thinking, it would be better to have a very small level that could lay across the breech but I don’t have one that small.
Regardless, the rifles I’ve done this way shoot accurate.

[35 shooter]

This is why I love GTA. I pick up pertinent to me info all the time here. I was considering the Mac 1 mounts.... now I Know that’s the one I want!

[Techie]

Don't forget this mount that clamps only onto the breech, not the barrel.  It's what I have.

or here:
https://www.airgundepot.com/air-venturi-intermount-benjamin-sheridan-multi-pump-rifles.html

[RBQChicken]

I use two bubble levels. One on top of the mount and one on the inside of the trigger guard. To my thinking, it would be better to have a very small level that could lay across the breech but I don’t have one that small.
Regardless, the rifles I’ve done this way shoot accurate.

Would these work?

[Techie]

In a URL link like the above post, you can delete everything from the "?" on, so the link will be much shorter and still go to the same place:

[jakeadks]

Thanks all,
In response to the MAC1 and air venturi, any weight on them will create torque on the soldering since they affix to the barrel or breech. I think I'll be able to permenantly shim the BA. I set it up this afternoon and found that my POI had shifted drastically moving from an air venturi to this, the BA mount. Super windy though, I'll wait for a calm morning to learn if the mount is crooked. Cant, that's the word I couldn't remember in the original post. Must be getting old ('96). The BA mount does not address the cant issue, at least on my rifle, until shims are added, but then it seems solid. Only time will tell. Hawke 2-7 inbound, seemed well matched to the rifle.

[RBQChicken]

In a URL link like the above post, you can delete everything from the "?" on, so the link will be much shorter and still go to the same place:

Good to know. Thanks!

[Habanero69er]

Randy, those levels might work. You should probably measure the size of your breech to be sure. The one's I have are small, but have a magnetic base on them which makes them too wide to fit the breeches on my Benjis & Dans.

Techie, good info on those super long links.

Jake, in all due respect, your assumption about the IA mount is wrong. The clamp on the mount is the size of the barrel so it doesn't torque the barrel. No shimming needed to make it to the right size or prevent slippage. I've yet to hear anyone say they've experienced barrel separation due to the IA mount.
Timmy Mac is a second generation airgunsmith & has forgotten more about airguns them most of us will ever know. I highly doubt he'd sell a mount that would damage the same rifles he's put his life's work into saving & repairing.

[GarthThomas]

Thanks for the mention of the breech mount, Ive been looking for something like that to use on the barrel of my qb57. I just ordered it this morning.

[moorepower]

This is the first person I have heard or read that had issues with the BA mount?