Identify Weaver Mount-Screw Thread

Improving and repairing firearms. Rifle bedding, barrel work, stock replacement and other ways to improve your firearms.

Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 06 Jun 2018, 7:17 pm

I want to replace the screws in the Weaver mounts which carry my recently refurbed Leupold. The slots are of varying widths, which is why my carefully ground screwdriver has jiggered one.
But I need to know the thread. (I presume) So how would I go about finding out?
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by bladeracer » 06 Jun 2018, 8:30 pm

Wm.Traynor wrote:I want to replace the screws in the Weaver mounts which carry my recently refurbed Leupold. The slots are of varying widths, which is why my carefully ground screwdriver has jiggered one.
But I need to know the thread. (I presume) So how would I go about finding out?


Do you mean bases or rings?
A thread pitch gauge, or email Weaver and ask them.
Brownells might list screws specifically for weaver which might indicate the screw sizes.
Practice Strict Gun Control - Precision Counts!
User avatar
bladeracer
Field Marshal
Field Marshal
 
Posts: 12655
Victoria

Re: Identify Weaver Mount-Screw Thread

Post by straightshooter » 07 Jun 2018, 8:21 am

If you mean the screws that attach the base to the receiver then mostly they will be 6-48 and in some cases 8-40 or 3.5x0.5 but they will require a specific countersink.
If you mean the screws that attach the pressed metal upper to the lower alloy ring then they are 6-40. In my opinion those pressed metal style rings are one of the worst rings ever manufactured. If you really want to you should be able to find 6-40 allen screws on our old (dubious) mate ebay.
It is also possible to recondition slotted screws if they are not too damaged.
Hold the threaded part of the screw in a vice held between two pieces of wood or drill a neatly fitting hole in a piece of hardwood and screw in the screw.
Now lightly tap the face of the screw with a small hammer until all the displaced metal moves back to where it should be
It would have helped if your description was a little clearer.
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: Identify Weaver Mount-Screw Thread

Post by Rod_outbak » 07 Jun 2018, 9:36 am

Screw sets:

https://www.brownells.com.au/index.php? ... anu_id=798
(Torx head)

https://www.brownells.com.au/index.php? ... nu_id=1350
(traditional styled slotted heads)

Attached images are my 2 screw sets; One from Williams, and one from Pachmayr. The later Pachmayr sets as listed on Brownells seem to use Torx heads.

From a quick look, I dont think my Pachmayr set have any countersunk heads in the set; the Williams set does.

I hope this helps.

Cheers,

Rod.
Attachments
DSCN2053 (2).JPG
DSCN2053 (2).JPG (309.44 KiB) Viewed 7037 times
DSCN2051 (2).JPG
DSCN2051 (2).JPG (386.34 KiB) Viewed 7037 times
DSCN2049 (2).JPG
DSCN2049 (2).JPG (339.68 KiB) Viewed 7037 times
DSCN2050 (2).JPG
DSCN2050 (2).JPG (371.46 KiB) Viewed 7037 times
---------------------
Sharing the extreme love with cats in Outback QLD
Rod_outbak
Corporal
Corporal
 
Posts: 494
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 07 Jun 2018, 10:16 am

Thank you and sorry for the confusion :oops: I will do better next time. Going with the cheeep ebay option for now thanks straightshooter :thumbsup:
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 11 Jun 2018, 6:59 pm

straightshooter,
I ordered the 6-40 just like you said. They arrived today two days early and fitted perfectly :D
Thanks mate :thumbsup:
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 12 Jun 2018, 7:08 pm

straightshooter wrote:If you mean the screws that attach the pressed metal upper to the lower alloy ring then they are 6-40. In my opinion those pressed metal style rings are one of the worst rings ever manufactured.


I found out today how absolutely right you are. It was when my ring lapping tool was put to use this p.m., that I discovered that these rings put a bend in the scope :evil: :shock: No wonder the scope needed a trip to Nioa's vet ;) The machined rods that come with the kit, simply point in different directions :huh: :crazy:
I have attacked the ring-bottoms with heavy pressure and #240 grit paper and the out-of-true condition, is much improved. Will do some more tomorrow otherwise I'll be going shopping.
Too bad about all that, after I had done a great job of repairing the base-screw slots and trimming the new shcs for the rings :(
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by straightshooter » 13 Jun 2018, 8:05 am

Wm.Traynor wrote:
straightshooter wrote:If you mean the screws that attach the pressed metal upper to the lower alloy ring then they are 6-40. In my opinion those pressed metal style rings are one of the worst rings ever manufactured.


I found out today how absolutely right you are. It was when my ring lapping tool was put to use this p.m., that I discovered that these rings put a bend in the scope :evil: :shock: No wonder the scope needed a trip to Nioa's vet ;) The machined rods that come with the kit, simply point in different directions :huh: :crazy:
I have attacked the ring-bottoms with heavy pressure and #240 grit paper and the out-of-true condition, is much improved. Will do some more tomorrow otherwise I'll be going shopping.
Too bad about all that, after I had done a great job of repairing the base-screw slots and trimming the new shcs for the rings :(


Something is not right.
The problem with this style of rings is that they effectively only have two points of contact between the ring assembly and the scope tube and were originally intended for use with steel tubed scopes like the ancient weavers where a lot of clamping force was feasible.
In the dark ages of benchrest some people would use a ball mill to make a shallow slot in the alloy base to thus provide three points of contact for the scope tube and in so doing eliminate the problem of lateral movement of the scope within the rings.
You can achieve a similar result by giving a single wrap of good quality electrical tape that gets compressed under the ring and provides a more secure fit within the ring assembly.

Have you considered that the indicated misalignment is due to any other reason before attacking the ring bases?
The ring bases are a linear extrusion and it is extremely unlikely they are out of true.
Two piece weaver and picatinny rails can be out of alignment.
Even one piece alloy rails can easily bend.
Bending forces can be introduced by haphazard positioning of the rings on the rail or in the assembly sequence.

If you give up with these rings then choose machined steel rings which are split across the center as replacements.
Avoid like the plague any that claim to be 1"/26mm compatible.
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 13 Jun 2018, 10:18 am

Thanks for replying, straightshooter.
Regarding the misalignment, I turned them 180 degrees and it was still crook. That leaves the bases and/or the alignment of the action holes. I could remove the two piece bases and check the holes and if they are OK, the bases could be turned round. This will keep me busy.
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 13 Jun 2018, 2:46 pm

Just finished honing out the ring-bottoms, three more times. Still dodgy and is more so in the horizontal plane. Vertically speaking, the alignment is not too bad but horizontally, it is persistently crook.
Been looking at Leupold's site because the scope is one of theirs; a 1.5-5X20. the site found a mount Sku 500001 and rings Sku 49901. They remind me of the old Hillver brand (olden days ;) ) Going to price them from Redcliffe. Prior to today my credit card debt was under control but this could make it a bit sick.
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by straightshooter » 15 Jun 2018, 7:42 am

The Bruce Hill era of Hillver mounts were simply copies of the original Redfield so called 'turn in' mount as are some Burris, Leupold and others these days.
The weakness of this system is that the mount is generally made from a free machining steel which tends not to be very durable under combined circumstances of heavy scope, heavy recoil and a lot of use.
What rifle and caliber are you intending to use it on?
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 15 Jun 2018, 1:16 pm

straightshooter wrote:The Bruce Hill era of Hillver mounts were simply copies of the original Redfield so called 'turn in' mount as are some Burris, Leupold and others these days.
The weakness of this system is that the mount is generally made from a free machining steel which tends not to be very durable under combined circumstances of heavy scope, heavy recoil and a lot of use.
What rifle and caliber are you intending to use it on?


30/06 Winchester Featherweight M70 Scope weighs 285grams. Ammo is loaded with 165 grain bullets.
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by straightshooter » 18 Jun 2018, 7:52 am

With the turn in style mounts, sooner or later the front dovetail attachment goes loose. With your setup it's likely to be much later if a good quality one piece base is used.
My suggestion is a Lynx (originally Hillver) one piece stud base, but I am bisaed.
Also, I recently bought a 44mag Marlin with alloy Talley rings that attach directly to the receiver. I don't have any practical experience with them but they look to have some merit if light weight and rigid attachment are concerns. I don't know what other rifles they are available for.
"Anything is possible if you don't know what you are talking about."
"There is no expedient to which a man will not resort to avoid the real labor of thinking." Sir Joshua Reynolds
straightshooter
Warrant Officer C1
Warrant Officer C1
 
Posts: 1263
New South Wales

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 18 Jun 2018, 9:12 am

Thanks straightshooter. I'll take a look at Lynx :thumbsup:
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Rod_outbak » 18 Jun 2018, 12:03 pm

A selection of alternative scope bases here:
https://www.rebelgunworks.com.au/search ... pe=product

Or maybe fit a picatinny rail?

Cheers,

Rod.
---------------------
Sharing the extreme love with cats in Outback QLD
Rod_outbak
Corporal
Corporal
 
Posts: 494
Queensland

Re: Identify Weaver Mount-Screw Thread

Post by Wm.Traynor » 18 Jun 2018, 1:47 pm

Thanks Rod :)
Wm.Traynor
Sergeant Major
Sergeant Major
 
Posts: 1644
Queensland


Back to top
 
Return to Gunsmithing