Will a Sako 75 .308 bolt be the same as a sako 75 .243????

woodystock

Active Member
Hello all, l hope you can help me. I lost my bolt a few weeks back out of my .243 as most of you's have prob read. I am having a nightmare trying to replace it, without the extent of sending it back to sako which is gonna be costly and time consuming- l may have no choice- however. I have found a sako 75 bolt for sale for a .308, and am wondering if it will be the same- lve been assured that the head space is the same, as is the action, l just need to wheather the locating lugs- and the sears (not sure what that is) are identical, or can be modified by a gunsmith with not too much hassle.
So can l ask if anyone has a sako 75 in both .243 and .308 if they can compare bolts- or even try them for fitting- not forgetting to take them straight out afterwards?
Mine is a 75 hunter with heavy walled barrel if that makes any difference at all.
Please let me know your findings.
Regards, Chris.
 
It sounds like it should fit but don't just stick it in and fire a round! Whenever a bolt is changed, the rifle's headspace should be properly checked using SAAMI specification calibre specific headspace gauges. A good riflesmith will do that for you. (Not all RFD's are up to this!- Very few actually have the gauges) It may cost a bit but better be safe than sorry.
Good luck
Ian
 
The 308 bolt will be identical to the 243 bolt. However, as stated, you need to check headspace. This can easily be done with a set of "go/no-go" gauges from midway, should cost a fiver. The headspace should be fine, but still needs verified.
 
Go / No Go guages from midway are circa £35 each.

The 243 Win and 308 Win have the same headspace dimensions (as does 260 Rem and 7mm-08)

No two rifles are exactly the same.

Ive taken apart several Sako 75's, Tikka 595, 695, T3 et al for rebarrelling and they ALL have different headspace dimensions and barrel tenon lengths.....

At the minimum - if the bolt fits, you may need the chamber "setting back" (the barrel tenon elongating then machining to length) then the chamber re machining to correct headspace.....
 
Redmist,

How do Mauser, Blaser, Sauer etc. Breakdown rifles manage when the same bolt and head feed .243 up to 9mm bullets, not just cartridge?

Stan
 
Redmist,

The same magazine and bolt feed anything from a "short bullet to a long bullet".

Machine tolerance? Just trying to understand why multi barrel rifles can share a bolt but single barrel rifles can't.

Stan
 
Next level up is a custom rifle.

The Sako 75 bolts may indeed be able to be swapped bettween rifles, most Sakos ive seen have had .015" bettween end of bolt and rear of barrel (thats alot, I do mine with .005" clearance)

That means theres .010" of case head unsupported - doesnt sound much, but if your looking at stretching the best out of a rifle you want minimum clearances.

Headspace - you want 0 or as close to as possible - the difference bettween go and No Go is circa .004"

Not alot at all.


If the replacement bolt is worn or well used, this could easily put the rifle out of or over toleance for headspace.


only way to see is buy go / no go guage and use with replacement bolt.


Where are you in country?


Probably best to go to a riflesmith with guages and have it checked ,,,,,rather than do yourself.

Unless you know what your doing - apologies not meant to wind anyone up.
 
Yes thank you lads, l agree safety is paramount here- l am willing to take it to a rifle smith to have it checked, l am in north east england so l think border barrels could be my closest riflesmith here.
Thanks for advice, regards , chris.
 
When I had to buy a new bolt for my 595 Tikka, I had the head space checked it was found to be with in SAMMI no problems.

ATB

Tahr
 
On the sauer, blazer and Mauser m03 the bolts actually lock into the barrel, rather than on the receiver, thus very much easier to get correct tolerances. On more traditional designs, eg Sako, Remington, Mauser 98 etc the bolt locks to the receiver, with the barrel then screwed into the reciever giving lots more room for error.

A 308 bolt will be the same nominal dimensions as a 243, but before you fire it have it checked with go / no go guage by a gunsmith who knows what he is doing.
 
cant see how they would manufacture lots of different bolts and rifle blanks as that becomes expensive.
can they really be that far off each other when reaming chambers and screwing barrels to actions?

makes you wonder how they manage to fire factory ammo within similar tolerances straight out of the box if they are as unique as described above
 
Once you have had this work done, dont forgat you will need to have the rifle retested at the Gun Barrel proof houses in either London or Birmingham.
You will need to have this done firstly as it makes common sense and also it is a requirement should you ever sell the rifle.
Hope all goes well and you resolve the bolt issue.
 
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The real problem is that if your receiver/barrel is at one extreme of the tolerances and the bolt at the other the combination may be too far out, this is why you check them. The ammunition manufacturer works on the assumption that the rifle will be within tolerance to supply sufficient case support.

David.
 
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Just a side note, regarding the Sauer. The 202 model I own in both .243 and 7x64 have very different bolts. The former locks on three lugs, while the latter has six. The cost of the bits made it almost the same as owning another spare rifle, hence my two 202's.

On the sauer, blazer and Mauser m03 the bolts actually lock into the barrel, rather than on the receiver, thus very much easier to get correct tolerances. On more traditional designs, eg Sako, Remington, Mauser 98 etc the bolt locks to the receiver, with the barrel then screwed into the reciever giving lots more room for error.

A 308 bolt will be the same nominal dimensions as a 243, but before you fire it have it checked with go / no go guage by a gunsmith who knows what he is doing.
 
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