Tikka M55 (LSA 55) sight thread pitch

BSAMarty

Well-Known Member
I have just acquired an old Ithaca LSA 55 which is made by Tikka and identical to the Tikka M55. It has been neglected for at least a decade and I am trying to restore it to hunting use.

It doesn't have any front or rear sights. Ideally I would like to find some sights, otherwise I would like to get some plug screws and plug the holes.
I cannot find a screw that fits. Does anyone know the thread pitch on these?
A 6-48 is too small and a 8-40 seems to big (or maybe just too coarse?) Any help is appreciated. Thanks
 
I have fore and rear open sights, with screws, for an M55 tucked away somewhere. Not sure how I'd value them or if posting to Canada is a viable proposition.
 
Most European Firearms will use Metric threads, certainly post war. With all firearms the only way of really knowing what threads are used is to measure them accurately, and a process of trial and error.
 
I have fore and rear open sights, with screws, for an M55 tucked away somewhere. Not sure how I'd value them or if posting to Canada is a viable proposition.
HI, if you want to sell them please advise, posting to Canada should not be an issue.
 
M5 is probably too big for sight retaining threads.

You're more likely looking at something around M3.5

 
M5 is probably too big for sight retaining threads.

You're more likely looking at something around M3.5

the holes shown in the linked picture - copied here - are 6-48 thread - though the article says they are 3.5m

because the LSA 55 (which is mechanically identical to Tikka 55) was made to be imported to the USA, I'm wondering if they were tapped with imperial threads

And those are not the plugs I need, I need the ones for the iron sights.
 

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the holes shown in the linked picture - copied here - are 6-48 thread - though the article says they are 3.5m

because the LSA 55 (which is mechanically identical to Tikka 55) was made to be imported to the USA, I'm wondering if they were tapped with imperial threads

And those are not the plugs I need, I need the ones for the iron sights.

I know those are the scope mounting threads but thought that the sight mounts would be similar. Try M3.5 or maybe even M4 - I doubt that the screws will be imperial.
 
I know those are the scope mounting threads but thought that the sight mounts would be similar. Try M3.5 or maybe even M4 - I doubt that the screws will be imperial.
Thanks, I will try M4, M5 too
Seems odd though that the optic mounts are imperial and the iron sights mounts metric?
 
I have just acquired an old Ithaca LSA 55 which is made by Tikka and identical to the Tikka M55. It has been neglected for at least a decade and I am trying to restore it to hunting use.

It doesn't have any front or rear sights. Ideally I would like to find some sights, otherwise I would like to get some plug screws and plug the holes.
I cannot find a screw that fits. Does anyone know the thread pitch on these?
A 6-48 is too small and a 8-40 seems to big (or maybe just too coarse?) Any help is appreciated. Thanks
I have M65s, M595s, and M695s in Lefthand, but the LSA55 & M55 models were only ever made in Righthand. For some reason all LH models were fitted with sights, except the heavy barrel M65 Continental. I took off all the fixed sights, and sold them to Brithunter, so I know all mine use the same foresight plug screws.

The M595/M695 receiver and bridge is drilled and tapped for US Weaver base mount screws. That makes sense, but I don't know why Tikka bothered when there are integral dovetails.:)
 

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Thank you for that information.
I have a M4 screw and that seems to be the correct diameter, except the screw is a coarse pitch and clearly the barrel was tapped in a fine picth
So M4 fine pitch is probably what I need.

SO now the question is, where do I get those?
 
I have M65s, M595s, and M695s in Lefthand, but the LSA55 & M55 models were only ever made in Righthand. For some reason all LH models were fitted with sights, except the heavy barrel M65 Continental. I took off all the fixed sights, and sold them to Brithunter, so I know all mine use the same foresight plug screws.

The M595/M695 receiver and bridge is drilled and tapped for US Weaver base mount screws. That makes sense, but I don't know why Tikka bothered when there are integral dovetails.:)
This is good information. I found a parts diagram for the 595-695 and it indicates the foresight plug screws are in fact M4x2.5
Thank you for this

And M3.5 for the receiver screws (on the UK - Euro models)

Now I just have to find them....
 
This is good information. I found a parts diagram for the 595-695 and it indicates the foresight plug screws are in fact M4x2.5
Thank you for this

And M3.5 for the receiver screws (on the UK - Euro models)

Now I just have to find them....
A little late to the conversation , but you could try Western Gun Parts in Edmonton AB . I'm pretty sure they can help you out .

AB
 
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