Savage 99 head space

[zephaniah]

How do you check the head space on an old (1917) take down 250-3000 ?

[GunnyMack]

When checking/setting head space you would strip the bolt, no extractor, no firing pin. Both can give a false head space.
Insert the GO or NO GO or FIELD gauge and close the bolt( lever in the 99). If it closes on the NO GO or FIELD you have excessive head space. Its quite simple to check.

[zephaniah]

Thanks, GunnyMack, I didn't know if there was a way to do it without gauges. The gun is in really good shape, doesn't appear to be used or abused much. When taking the barrel down it seems tight at the beginning, as it should be. The bore is a little dark and has some copper fouling and what might be small pitting. I'm thinking of fire lapping later but want to check everything out first. Any advice on the lapping would be helpful.

Thanks much for your help and expertise.

Happy New Year

Kindest regards,

Zeph

[GunnyMack]

Start by scrubbing the bore, lots of elbow grease. If still dark try JB BORE paste.
Of course shoot it for accuracy, might be surprised it shoots fine even with a dark bore.

If the gun is tight I'd be surprised if the head space is off.

[zephaniah]

Thanks GunnyMack,

I kind of had the same thoughts about the tightness of the lockup. The shape it's in, I don't think it was used very much. It has marbles sights all around including the tang peep. Still has most of the original finish also.

Thanks for your insights.

I can't wait get it out and try it.

Regards,

Zeph

[GunnyMack]

Keep us posted on how it shoots, pictures too!

[BenT]

You can put a piece of masking tap on the base of a sized case or brand new round. Close the action. Add another piece and then close action, keep adding a piece until you get resistance when closing. Then peel the tap off and measure the thickness of the tape. If it closed on two pieces of tape but not 3. Then measure the thickness of 2 pieces of tape. Then you will have range of the head space. You could also try a piece of plasitgauge on the case head. Just make sure you have the correct range.

[zephaniah]

Thanks BenT,

I didn't think of something as simple as that. I guess I AM getting older.

I appreciate it,

Best regards,

Zeph

[FLINT]

you could also shoot it and see if the primers are backing out. I have an old winchester 1894 that had the barrel replaced 75 years ago, and rounds shot in it have slightly protruding primers. I don't shoot it that much though, so I'm not concerned.

[zephaniah]

thanks Flint, when it warms up I'll watch for that.

Zeph

[Malamute]

A couple things to keep in mind, using a cartridge, its never mentioned how one knows where the individual cartridge falls in the exact size/spec range. Most commercial ammo is on the small side of spec to easily chamber in all guns. without having a baseline size of that cartridge, all you are measuring is how that individual cartridge fits the chamber, not if its right or in spec. Measuring the rim on a rimmed shell makes it easier, but a rimless round one would need an accurate cartridge gauge, otherwise you arent really learning anything specific to the actual headspace specs.

Look up the saami cartridge and chamber specs drawings on a given cartridge, theres a range of acceptable specs, NONE of it is a single exact number. A max spec chamber and a minimum spec cartridge can give max spec clearance, but unless you have an actual known number to work with, like measuring rim thickness or a cartridge gauge, or a headspace gauge set, you can chase your tail and not really know much regardless of how much tape or shims one ends up with on the back of the random, unknown size shell..

Many times a primer backing out isnt a headspace issue, but a low pressure issue, Its in all the older loading manuals, but never seem to be brought up in "checking headspace because my gun is backing out primers" discussions. A gun can be entirely within spec, even tight spec, and still back primers out. Its part of normal operation but with insufficient pressure to push the case head back against the bolt face if the case grips the chamber wall well and doesnt stretch the case. Case hardness, chamber wall smoothness or lack of, will play a part.

I have a 1920s 94. It backed primers out. Must be bad. I had a good machine shop carefully weld up the back of the bolt and I carefully hand filed it until the bolt would barely close on a shell. Hot dog! Perfect headspace. right? It still backed primers out. i started looking into the whole thing, and my conclusions are the above paragraphs. It means pretty much nothing by itself.

[zephaniah]

Very good post. Lots of variables I didn't think about. I think I'll not try that approach.

Thank you very much for the heads up.

Kindest regards,

Zeph

[BenT]

Malamute is correct. If you want to be sure rent some go an no gauges. I use the masking technique to just tell me if it is in a safe range.

[zephaniah]

thanks I appreciate the advice.

Zeph