What is the screw size for the upper sideplate screw on a 1954 vintage 357 magnum? It looks close to a 3-56, but I am not certain. Thanks, Ron

Think it is 5-44. It is not a "normal" pitch. Ace hardare stores often have a set og gun screw drawers that have a selection you can try. Usually a bit long, but easy to shorten.

The large top side plate screw is 4-48. No, ACE does not have them.

__________________
Mike 2796
SoFo Bunch member

4-48 seems right. I have the screw, but need to clean up the threads on the frame so wanted to get proper size tap. thanks

I'm not sure about the proprietary side of mentioning someone that provides the screws but there is a guy on the internet that sells the sideplate screws in either one at a time or all at once. I like to keep a full set on hand, they fit perfectly and are nicely blued. One could always take a NOS screw and lightly buff the surface to achieve the proper wear to make it match perfectly. I believe I located the guy by simply going into Ebay and entering the item, once located I have then simply gone directly to his webstore. I believe a full set to be around $20, they are very nice.

Yes, the bug screw (upper) does have a 4x48 thread (pre- and post-war). Others are 5-44, at least post-Feb 1942.

Thanks to all for help. Now to find a 4-48 tap. Ron

McMaster Carr supply. Look on the net. Aint cheap. Mike

__________________
Mike 2796
SoFo Bunch member

New scew if needed on ebay for $3.99

Just search Upper Sideplate Screw

A 4-48 tap is about $7.00

Do you have a T Handle Tap Wrench to hold the tap?

__________________
NEVER GIVE UP YOUR GUN

MSC industrial has the Taps for < $6.00
JIM...............

__________________
SWCA # L-1911

Brownells has the tap and now you can sign up so there's no shipping charges for one small part.

__________________
Jim
S&WCA #819

If you get a tap it will have to be a bottom tap. The thread depth is too short for any other style.

__________________
Tom
NRA Pistol Inst

Actually a starter tap with the point ground off will be safer.

Bottoming taps will cut full thread depth (as they are meant to do, but are notorious for making threads a bit oversize. You don't want the screw coming loose or stripping out the original threads in the hole when tightening the screw.

__________________
Jim
S&WCA #819

Thank you one and all. Upon closer examination I discovered that the threaded frame hole is fine....no tap needed. The problem is with the spare Victory model screw that I intended to use. The Victory screw thread seems to be a bit different than threaded hole. I tried the screw from my 1950 K-22 and it works just fine. So I will need to buy a different replacement screw. Thanks again for all the input. Ron

Some things to be aware of:

The sideplate and stock screws specification change order of March 4, 1942 was just that: a specification change in the standardization of tolerances for SCREW DIAMETER. A change from old S&W 'smaller minimum diameter' tolerance to the larger minimum standardized tolerance of the screw diameter (no, the 44 threads per inch did not change nor did the #5 stock screw, NOR the bug screw or upper sideplate screw which is a 4-48).

Therefore, there CAN BE a difference between 'pre-change' and 'post-change' screws and they CAN measure different diameters. Sometimes they are interchangeable and sometimes not. After 3/4/42 K & N stock screws became #5-44 NF with an upper OD tolerance of .125" and usually measure .122”+or-.

Change order April 19, 1943 to shorten the K frame bug screws to .181.

It appears the K bug screw was on a different evolutionary trajectory than the other frame sizes during a specific timeframe and may explain the different K bug screw diameter from other frame bug screws as well.

I would mic (measure) the bug screw that works for you and try to get one with the same diameter threads.

__________________
Jim
S&WCA #819

Jim, thanks for all the helpful info. The bug screw from my K22 mikes at .099 whereas the Victory bug screw mikes at .103 so that explains why the Victory screw won't work in the 27. Now to find that elusive .099 screw....Thanks again. Ron

You might want to try "club gun fan" here on the forum. He has a large quantity of NOS small parts that were salvaged from the scrap yard by a former employee and then purchased by him.

Not sure what time frame they are from but pretty sure he has some screws as well as sight blades.

__________________
James Redfield
LM #497

Tried to PM "gunclubfan" but Forum says "suspended" so couldn't send PM. Any ideas?

Try "club gun fan" instead.

__________________
John 3:16
WAR EAGLE!

Same problem with "club gun fan"....."suspended"

Rec. a tap and die set for 4-48 upper screw. Worked like a charm. Best

__________________
Mike 2796
SoFo Bunch member

I once had an experience in which a newer bug screw was a loose and sloppy fit in the threaded hole of a 1920s K-frame. But it tightened OK, I just didn't overtighten it for fear that the threads would strip.

You can't do much about a tap, but there are dies which have an adjustment screw for slight diameter differences. Both McMaster Carr and MSC proably have them.

__________________
Tom
1560

Was able to find a perfect match for needed screw from Gun Garage out of Arkansas. Nicely made reproduction and fits like a glove. A little pricey at $8.99, but worth it to end the search. Ron

I bet that check for $8.99 did not hurt at all.

__________________
Mike 2796
SoFo Bunch member

After looking at that empty hole for over a week that $8.99 really did not hurt at all. Now that little 3-1/2 inch pre 27 looks like a million bucks.....well, maybe seven hundred bucks anyway. Ron