Loose stock screw HW98

Torque Spec And Stock Screw Modification Questions:

Same problem set, but different brand / model gun… I finally got around to shooting my new to me vintage RWS54. I had a few different style of pellets to shoot and “test”. I was particularly not happy with my brand new recently purchased RWS pellets. A fellow club member had earlier given me a partial tin of his JBS pellets (177 cal, 8.44 gr) and the gun shot it really well and used it to get my scope dialed in and to validate zero at different distances. I then tried my RWS sample pack pellets and groups were all over the place… the witness marks on the scope base and rings were unchanged. No movements there. Realized I read someone’s posting to check stock screws. Yep… loose… like way loose. Gun rattling in the stock loose.

With only my Leatherman available, I got it somewhere back to just tight. Shot a few more groups with the “good” JSB pellets…then ran out…then went home to do proper maintenance and “repairs”. i had lost confidence with the RWSs… will shoot them later.

So… anyone know if I can swap out the Phillips heads screws/bolts? i have a calibrated torque wrench and will have better control with a hex or torx system than the cross head. Lastly, what should be the torque spec for these wood stocks and the proper order to tighten? Same questions for a HW35 and AA TX200.

TIA
Bob

I used to shoot a RWS 54 in FT (still own one). That RWS 54 is a different beast compared to HW97s and TXs. Untuned...those recoil sleds are not fun to adjust. Even tuned, it'll drive you crazy chasing down POI shifts (sooo many possibilities). You probably already read this one...but for those who haven't

Steve Herr's full tune of a 0.20" cal DIANA 54

and don't get me started on finding an appropriate FT scope for that beast.

It can be done and conquered...just not by a mere mortal like me.
Good luck.
 
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The best solution is to get wrid of the springwasher and place a counter nut on the backside. No need to use loctite or anything else.
Easy to remove and never lose screws anymore.

I will place a picture later.
That'd be a good idea on the older guns with the welded stock hanger brackets. I'm not sure the newer guns have enough space between the bracket and the cocking arm for a nut. A picture would be great. Always looking to learn new things.
 
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The promised picture.
This is a HW77k. Done it also with other types.

20230422_214034.jpg


When you leave the springwasher out, the screw wil be long enough to put a nut behind it.
 
The promised picture.
This is a HW77k. Done it also with other types.

View attachment 350383

When you leave the springwasher out, the screw wil be long enough to put a nut behind it.
Thanks that looks great. Love the laminate BTW. The newer 95 family guns (and I believe the 80s) have a cast stock hanger bracket that's thicker than the older welded brackets. I could check mine for clearance if the relevant guns weren't all packed up for my move. You definitely a good idea there I'll try it on my 97.
 
Thanks that looks great. Love the laminate BTW. The newer 95 family guns (and I believe the 80s) have a cast stock hanger bracket that's thicker than the older welded brackets. I could check mine for clearance if the relevant guns weren't all packed up for my move. You definitely a good idea there I'll try it on my 97.
Did not know that Weihrauch changed it.
 
This might seem a bit radical,especially for a quality air arm but could come in handy for other items having the same issue. Bugger up the threads a little bit. Score the threads on 1 side. This technique is referred to as an interference fit. I've done this to screws that have to go in a worn or oversized tapped hole.
Very bad idea imo.
You destroy the tread when you unscrwew it a few times.
It is a good solution when you never will unscrew it.
 
LocTite is not a great solution. Sure it may keep the screw from backing out.

But the problem with the cured LocTite is that you can't feel if the screw is actually still providing clamping force, or if the fastener is simply bound in the threads. Having a better "mechanical" type locking feature is a better approach IMO since keeping an eye on their tension is important.

One thing I have done on guns without metal screw cups, is make Delrin washers to replace the factory star washer and flat washer combo. The Delrin seems to act a bit like a spring and keep a little tension under the screw head, and engages in the serrated interface on the underside of the screw head. It works well for me. I make them about .090" thick.

My preferred approach that I use on my guns, is to make fitted bronze/steel screw cups with the Delrin washers. This works excellent on the guns I've put them in.
 
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I make brass bushings as I stated. Then polish/blue a Allen flat head. Degrease as stated. Blue Loctite. Just a drop. Again as stated, Do Not Over Tighten. Just snug. I like the brass bushing because more surface is in contact to the wood. They never loosen up. Easy to make but can be purchased on other sights.View attachment 350303
Question Bear ! Are those are tapered screws or did you go flat head to keep the
head flush, or lower than the stock forearms surface? I've made brass washers
for both my Feinwerkbau 124D and various Diana 34's I've owned and they do
help.
 
Use the CA glue to harden the wood first. Then up grade your screws from the crappy grade class one threads on the factiry screws. Get a good quality cap head screw, class 2 thread screw and the threads will be a better quality and hold more securely. I still clean my threads then add a micro dot of blue loctite, no more. last did my TX screws three years ago, still tight....
 
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Question Bear ! Are those are tapered screws or did you go flat head to keep the
head flush, or lower than the stock forearms surface? I've made brass washers
for both my Feinwerkbau 124D and various Diana 34's I've owned and they do
help.
They are tapered. The taper matches the taper on the bushing. If they ever did start to loosen the head would not damage the forearm hole in the stock because the head is at the surface. I’ve seen a stock crack from a loose screw.
 
I second the motion of a flat washer under the star type. This tremendously spreads and evens-out the compression load on the wood - an effective poor-man's version of a milled cup. You might also try using a split-type lock washer in lieu of the star.

Another thing that may help is to check that the stock inletting is smooth. New guns will often have raised grain, varnish runs, or other imperfections in the fore end that prevent the receiver tube from bedding evenly. A raised spot acts as a sort of fulcrum, exaggerating movement when firing and accelerating loosening the screws.

Finally, to follow up on MOSOSODBOB's post above - try different pellets. Skirt sizes vary a surprising amount, which affects when and how the pellet starts down the barrel; some ammo simply shoots more smoothly than others. RWS has about the biggest skirts of any brand, and will often cause piston bounce-back in a gun with a tight breech (which most HW's have). JSB skirts are smaller, thinner, and made of softer lead, which works much better in many guns.
 
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I second the motion of a flat washer under the star type. This tremendously spreads and evens-out the compression load on the wood. You might also try using a split-type lock washer in lieu of the star.

Another thing that may help is to check that the stock inletting is smooth. New guns will often have raised grain, varnish runs, or other imperfections in the fore end that prevent the receiver tube from being evenly bedded. A raised spot acts as a sort of fulcrum, exaggerating movement when firing and accelerating loosening the screws.

Finally, to follow up on MOSOSODBOB's post above - try different pellets. Skirt sizes vary a surprising amount, which affects when and how the pellet starts down the barrel; some ammo simply shoots more smoothly than others. RWS has about the biggest skirts of any brand, and will often cause piston bounce-back in a gun with a tight breech (which most HW's have). JSB skirts are smaller, thinner, and made of softer lead, which works much better in many guns.
" JSB skirts are smaller, thinner, and made of softer lead, which works much better in many guns."

Same with the Air Arms pellets. My 124D gets 10-15 fps higher with AA pellets than with equal weight
JSB's. And just as accurate.
 
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The HW98 has a flat washer on bottom then the star this was factory. I cleaned both threads in/out applied blue lok tite just as before and seems to be holding great.
I believe the key was cleaning the threads.
Thanks
And also be sure to shake up the loctite before applying as it does seperate. If the loctite has not dried after a few days it was not properly mixed when applied. No it doesnt get rock hard, sort of like a cured caulk compound. A small brass brush also helps in cleaning the threads, removes any crud ( old loctite) and the acetone removes any oil residue that would prevent the loctite from drying and holding.
 
" JSB skirts are smaller, thinner, and made of softer lead, which works much better in many guns."

Same with the Air Arms pellets. My 124D gets 10-15 fps higher with AA pellets than with equal weight
JSB's. And just as accurate.
Same in my TX, the AA pellets are slightly better than their JSB cousins
 
I have a lot of lower-powered older springers, and the Air Arms Falcon and JSB Exact Light (both 7.3 gr roundheads) have become favorites. In most guns they are faster than the lighter RWS Hobby (6.9 gr flathead) which shows the diff that bigger, stiffer skirt can make.

The RWS stuff has its place though. Some HW 55's made before the mid 1960's have a tapered breech leade, for example, and in those I don't even bother trying anything but RWS. Also great in many old tap-loading guns - the hole through the tap is slightly tapered and the bigger skirts seal better.

Again, always pays to check out different pellets!
 
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I have a lot of lower-powered older springers, and the Air Arms Falcon and JSB Exact Light (both 7.3 gr roundheads) have become favorites. In most guns they are faster than the lighter RWS Hobby (6.9 gr flathead) which shows the diff that bigger, stiffer skirt can make.

The RWS stuff has its place though. Some HW 55's made before the mid 1960's have a tapered breech leade, for example, and in those I don't even bother trying anything but RWS. Also great in many old tap-loading guns - the hole through the tap is slightly tapered and the bigger skirts seal better.

Again, always pays to check out different pellets!
Thanks for your insightful comments … my 35+ year old Weihrauch HW35 shot the East German pellets from that same time frame really well… even tho mal-formed and dented… also the RWS R10 from around 20 years ago as equally well… when I tried the recently purchased RWS pellets… they shot like crapola…I will pay more attention to the skirts now… Seems counterintuitive given how “well” the skirts of the new RWS sealed up the breech when compared to the DDR pellets… again.. learning.
 
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Use the CA glue to harden the wood first. Then up grade your screws from the crappy grade class one threads on the factiry screws. Get a good quality cap head screw, class 2 thread screw and the threads will be a better quality and hold more securely. I still clean my threads then add a micro dot of blue loctite, no more. last did my TX screws three years ago, still tight....
Who would be able to source these upgraded screws? Also size (length) thd pitch?
 
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