HW 90

[AJZ1952]

I've just picked up an HW 90. I've mounted a UTG 3-9x32 compact bug buster (comes with Picatinny rings) using a UTG low profile airgun to Picatinny/weaver rail adaptor. The recoil is so sharp on this rifle that I can't keep a scope located for more than a few shots. It's actually bent the rear of the rail adapter and the lock screw has deformed the mounting hole on the barrel. The cleats in the Picatinny rail are also deforming. I suppose there is a easy fix with a solid mount? Any suggestions?

[tjk]

Is it brand new?!? If it is and has the open sights, why not just shoot it with them and get used to the gun first. This will also give the rifle a chance to break in all the components including the internal 'inertia' plug that moves within the gas ram piston. The HW90/RX rifles do seem to come from the factory tuned, but a little breaking in goes a long way. You will also notice the shot cycle calming down a good bit and becoming less harsh. If you bought the ram used, it (the ram) may simply be over charged and a heavy duty one piece mount may be manditory in your case. It would be helpful if you could give some additional information about your rifle,.....age, owner history, post factory tuning, etc. These are great guns and are keepers if you like magnum power.

[Cliff]

Same issue on my HW90
I've  destroyed tweo Bushnell Trophy XLT scopes and am looking at the Hawke HK3271 which Hawke Tech says can run on this gun.

That said. I had to mount my scope mount using a custom lug to prevent slipping backward.
I'll try to take some pictures today and post them now that I actually have the scope & mount off the gun.

What I did was to locate a hole to tap with a 10-32 tap in the underside of the mount exactly over the line of  holes provided in the factory gun for  mounts with anti slip lugs.
Then I  modified a 10-32 allen bolt to fit the factory hole snugly.  This was easy I just took the little bolt to the grinder in a hand drill and spun it against the wheel till it was the right size.
Then I installed that in my mount and it fit the hole. Now my mount does not slide backwards with each shot.

I had prior installed a mount with a little lug exactly for this, but the lug was too "dang" small and acted just like a steel plow in soft earth,  plowing a furrow towards the rear of the gun, a little further with each shot.  Imagine my shock when I pulled the mount and saw that? 
It is an absolute necessity that the anti slip lug be about the same size as the hole to take advantage of all the surface area available.

If you want to spend the money on a smith, you can have a Rail permanently mounted to the gun. I've thought about TIG welding a steel rail on my gun.

This gun at factory setting is balanced. Releasing some gas is not a terribly great idea I don't think.  One  can do it but I think it's error.  But the things one has to do to use the scope mount rails.   Weihrauch really did leave too much  undone.  This gun should have come from the factory with a rail milled in the thing.

[Cliff]

Stop pin Lug  damage:




My modification to the scope mount



The larger diameter works

I'm getting a Hawke Sport Optics Eclipse SF 6-24x50  I am unhappy with Bushnell's products having sent their's back twice now
I'm also trying out a new scope mount the BKL 1-Pc Mount, 30mm six screw mount.

[robert w]

and I thought a Diana 54 ate scopes. wow you guys got a jewel in that respect. and I was thinkin about 1 of those 90's. my 54 gave enough greif with scopes. my ? whats the scope going to do when you stop the movement? I mean its going to take a darn hard jar when fired, id think those dampa mounts would be in order mounted in rubber . expensive? yes but so is buying a lot of glass.

[Bullit]

I've just picked up an HW 90. I've mounted a UTG 3-9x32 compact bug buster (comes with Picatinny rings) using a UTG low profile airgun to Picatinny/weaver rail adaptor. The recoil is so sharp on this rifle that I can't keep a scope located for more than a few shots. It's actually bent the rear of the rail adapter and the lock screw has deformed the mounting hole on the barrel. The cleats in the Picatinny rail are also deforming. I suppose there is a easy fix with a solid mount? Any suggestions?

I wonder if you mounted the Weaver adapter on your rifle using the wrong side of the mounting plate.  This would bend the plate after trying to "crank it down".  UTG offers mounts that are cut with 2 sides to accomodate the 2 different size's of dovetail cut angles on the rifles.  They ain't all the same, and need to be payed attn. too.  You have to remove the bolts and "flip" it over, to get the correct cut angle, for a proper secure fit.   You may well have only been relying on the stop pin to hold it.   It's happened before.

[Bullit]

Cliff...  I don't know, but by the picture of the stop pin hole you have.  I'm not sure the stop pin was ever set in the center of the stop pin hole.  The stop pin hole doesn't looked "peened" or elongated and scraped, but the back looks compressed from the stop pin getting screwed down onto it.  Like the mount wasn't tightened correctly and moved before the stop pin got properly set, and then tighten down the sideplate screws.  I'm going off the picture only, mind you.

[Cliff]

but by the picture of the stop pin hole you have.  I'm not sure the stop pin was ever set in the center of the stop pin hole.

Pix must not do it justice.  It's plowing a furrow.  Caught it before it did real damage.
 That gun killed the Bushnell Trophy XLT in less than one can of pellets.
Then I put a Dampa on and it took maybe a season to kill the next one.
I'd almost got used to the idea of paying $15.00 for return shipping to Bushnell for their 100% warranty every few months but for the fact that it takes them three or four months to put a new scope in the mail and return that.
The Bushnell will go on my Cheap Chinese 12 pound springer.  It'll be nice on that gun.
Oddly the lousy $39.00 Chinese gun can drive nails over and over again like it was a three thousand dollar gun and the spring rattles in the body, it's so loose.

[tjk]

Being an owner of these guns, I will have to say that when you install scope rings or a one piece mount, you really need to bear down on the dove tail clamping mounts. It would also be a good idea to check and make sure you have the clamping plate(s) turned the correct way. And by bearing down on the mounting screws, I mean no pu$$y footing around. Don't be afraid to put some serious torque on the bolts. I always replace the screws/bolts on rings and one piece mounts with quality hardware. Many times,...especially with the cheaper ring/mounts brands, they use inferior hardware in the fastening department. I have had my RX rifles set up pretty hot, and have rarely seen any movement at all once I've mounted glass. I had more issues with the scope itself sliding back than the mounting system. Thats a reletively easy fix as well. HTH's
PS About the only way most humans could ever damage the tube/dovetails by tightening their scope mounts would be by using an impact wrench or a cheater bar on the allen wrench. Simply think the old phrase "good'en-tite" during installation tjk

[Ahab]

tjk is right about shooting it with open sights for awhile. It will settle down. I ended up with a 5 screw 1 pc mount which appears to be holding up well. It sure packs a wallup using .25 cal 24.38 gr H&N Field Target pellets.