I would like to buy some Allen head type action bolt screws for my CZ 550 Magnum action. Since I'm coming to Dallas, do any of the Texans know where I can get some?

My wife is tired of me borrowing the kitchen knives when I take the stock off. Since I've got a bunch of Allen head wrenches left over from putting together the IKEA furniture in my living room this seems like the logical solution.

Wink,
I like these, and do them from time to time on big rifles, but haven't done it on the cz.

brownells sells a 20 pack , i think they call them socket hex head screws

http://www.brownells.com/aspx/ns/store/ProductDetail.as...EAD+LONG+BLANK+SCREW

just need to be threaded, cut to length, and harderned
jeffe

Jeffe, if that's an offer than I accept. What do I owe you?

heh, wink,
if someone will tell me the thread pitch and screw lengths, i'll cut them for you... don't have a cz handy... i'll even borrom a cz bottom metal and make sure they fit.

jeffe

Jeff,

As many times as I've posted the thread size for CZ's........I came up blank, I do remember its the same thread as 6.5 jap, cause thats what size my inletting guides are. I'm at my girlfiends so I can go out in the shop and look and no smart butt comments about CZ parts laying around , I put them back to gether.....well all but one plastic bag full of crap.

Jeff,

I would be interested in purchasing a set.

As I have found no source.

Many Thanks

HBH

who all wants some of these? I got about 16 or so screws in the shop... shipping (to france) will be quite a bit more than the parts!!

jeffe

Jeffe, I have a couple of USA mailing addresses so shipping costs aren't an issue. However, I don't have a way to measure the thread pitches. Maybe we can count on the force of the web to help us on this. Someone must have measured these or someone may know someone at CZ USA with this information. Instead of mailing them to me why not let me buy you a beer in Dallas in a few weeks and give them to me then?

The guard screws of the CZ rimfire rifles are M6x1.0 thread (6mm diameter, 1.0mm pitch) which is the same thread as used in Sako, Tikka, Howa, and many other rifles that originate in countries where the metric system is standard. (in other words, nearly every country on earth except the USA) A few European manufacturers – Anschutz, and Grunig and Elmiger, to name a couple - have used M6x0.75 guard screws in at least some of their models.

The Japanese Arisaka military rifle used M6x0.9 guard screws, according to Stuart Otteson, in his book ‘The Bolt Action’. This is a real bar-steward size, which does not appear in ANY listing of ‘standard’ metric threads that I have ever seen. The military designers of a hundred years back seemed to like using odd-ball threads for their guard screws, like 1/4inx22 in the Mauser 98, 1/4x25 in the ’03 Springfield, and 1/4x30 in the Enfield.

If the CZ550 does use exactly the same thread as the Arisaka, then the chances of finding substitute screws at an engineering supply house are just about nil. You would be lucky to even find a button die to cut such a thread with. The 1/4in socket head screw blanks that Brownells sell probably wouldn’t work out too well for either shank or head diameter.

Wink, in France you should be able to find M6x1.0 machine screws and/or bolts in any hardware store. Take one of your guard screws and a magnifying glass there, hold the two together, and see if the threads match.

If they do not, you might have to ask yourself if the joy of having socket head guard screws instead of the slotted head type is REALLY worth the effort.

I think I'll send an e-mail to Ed at AHR. I would guess that he would know.

thanks guys...
billy, when we have the beadblasting and bluing thing, i'll need to make up a couple sets of screws for these fellas.

jeffe

I'm in for 7 sets--I could send you one screw if you want Jeffe, but I'd like it back when you're done with it--let me know--I'll be leaving Tuesday AM for Christmas in Utah and won't be back until the 28th/29th....chris

I wonder if McMaster/Carr has these now that I think about this--I bet they do --I'll check it out---chris

www.mcmaster.com

go down to fastening and sealing and click on sockethead cap screws---only problem is will they seat rignt---

anyway let me know Jeffe if you want to use one of mine off one of my CZ's and I'll send it to you----chris

Thanks guys... I'll see if I can't "borree" a set of screws from billy.. don't really "care" about the length, just want to turn the heads so that they will fit in the bottom metal.

jeffe

i'll take a pair jeffe.

I don't know how far along the experts are in coming up with the Allen head triggergard screws for the CZ 550 might be at this point. I did try to measure mine however and came up with this:



Does this help? I know nothing about metal working or making screws of course but maybe this will help anyone who is trying to find some similar dimensions. The shank diameter seems to be 0.254" but the diameter at the outside of the threads seems to be 0.229". I'm no expert at measuring this stuff however so let me know if I have miss-measured.

Wink,
thanks. Let's be sure i can read this right.
Left hand screw
1.786 long
.395 head diameter
.155 head thickness

right screw
1.165 long
.392 head diameter
.177 head thickness

about .420 would cover either for thread length?

thanks
jeffe

jeffe,

Mostly correct.

Left hand screw
1.786 long (but it's got a rounded head so may not be a truly accurate read)
.393 head diameter (right hand screw is .392 so may just be tolerances or my measuring method)
.150 head thickness on the left, .177 on the right.

Thread length on left is .415 and on right is .373 but I suppose a little extra thread length wouldn't change anything. As is it's probably a little more than necessary but that would depend on stock thickness.

Unthreaded shank is .254.

I brought this back to the top because I wanted clarification on the screw size for the 550Magnum.

Which one is it???

6mm x .75mm like the 7.7 Jap,
6mm x .9mm like the 6.5 Jap, or
6mm x 1mm like Sako.

I have some notes scribbled down that they were 6mm x .75mm but I don't recall where this came from and it may not be correct.

Which is it?

Thanks,
GVA

jeffe, did anyone come up with the screw size, thread pitch, etc?

nope, but billy will be bringing a couple of his CZ's around for a bluing party, so I can meaasure them then
jeffe

Pretty sure the inletting pins I use on CZ's are .238 x 28. I havent measured a screw yet..........got to find one first

So Jeffe, did your bluing party ever happen?

nope... mother in law got sick and I spent most of the last week and weekend in shreveport...

hey billy, when you coming over?
jeffe

I am still interested. I have ask about this before and drawn a blank. I will check around at Reno this weekend.

Many Thanks

HBH

HBH, I am also still interested. If you find anything in Reno let us know.

Jeffe I would not mine two or three sets either !!

I do own a couple of CZ's

HBH & Wink,

If find out anything in Reno please keep me in the loop as well. I would appreciate that!

I have been looking for replacement screws for about a year now. The only person I know makes something similar is Jim Baiar of Halfmoon Rifle Shop. Naturally, these are for M70 & Mausers. I wonder if we got a large order together if he might make a run for us?

Regards,
Dave

I have a CZ 550 magnum that I would love a set of these for. If an order is being put together, I would very much like to be on the list for a set.

just emailed CZ for the thread pitch

quote:

Originally posted by jeffeosso:
just emailed CZ for the thread pitch

Stayed tuned. I called CZ while I was in the USA but was unable to locate anyone who knew. Let's hope they pass the question on to somebody with some techie knowledge.

quote:

Originally posted by GaryVA:
I brought this back to the top because I wanted clarification on the screw size for the 550Magnum.

Which one is it???

6mm x .75mm like the 7.7 Jap,
6mm x .9mm like the 6.5 Jap, or
6mm x 1mm like Sako.

I have some notes scribbled down that they were 6mm x .75mm but I don't recall where this came from and it may not be correct.

Which is it?

Thanks,
GVA

The guy at Brownells sent me some studs for use in bedding a CZ. They fit.

The screws threads are 7.7 Japanese

Try that at Midway!

Gee, I thought you guys were suppose to know this stuff!

Yep Will,
CZ confirms

quote:

thread pitch for the 550 magnum action screws?


That would be metric M6 x .75mm pitch.

quote:

Originally posted by jeffeosso:
heh, wink,
if someone will tell me the thread pitch and screw lengths, i'll cut them for you... don't have a cz handy... i'll even borrom a cz bottom metal and make sure they fit.

jeffe

El jeffe grande, you now find me in extreme expectancy as I believe

14 sets, total?

SHESH -- please verify that you would like these, and I'll order more screw stock and a die...

I'll turn the heads to size, leave them a hair long in length, polish and you guys want these blued, as well?

what sounds fair? 10 bucks a set, blued, too much?

jeffe

jefferso: I'd love to get a set as well. The $10 price tag seems okay to me. Please let me know what you plan to do.
Thanks ... Tom Purdom

Jeffe--I earlier said I wanted 7 sets, so I'll stick with that--that will give me two extra sets for future rifles--let me(us) know when and how you want the $$$--chris

the dang die is a big driver on the cost.. shesh..

polished or bead blasted?
jeffe

polished for me please and when do you want the money?