[chud]

May one of you professional's give tips on checking headspace on the kar98. Do I need to remove extracter from bolt like I do on the Mosin Nagant?

 

[zachary78]

I'm not a professional but I watched my gunsmith check the headspace on my k98. He pulled the bolt out of the rifle, removed the bolt shroud/firing pin, inserted the guage in the bolt under the extractor, gently pushed the bolt into the reciever, and then tried to close the bolt with just a little force to determine if the bolt would close on a field gauge. My bolt only went down about halfway, so he said it was good to go.

 

[chud]

Thanks Zachary78. After your info I can take it from there. By the way what's a good safe company?

 

[chasdev]

See above, but you don't have to remove ANYTHING.
You have to hold the bolt stop lever open as you install the bolt with the gauge held by the extractor claw and then the follower stops forward movement push down on it with a probe or screwdriver.
If your floorplate pops off without a struggle, do it that way.
If your extractor claw will not hold the gauge tight enough to keep it from falling out, then you may be able to feed the gauge into the mag and treat it as if it was a round holding the nose of it to the rear as you slide the bolt forward.
I found one yesterday that would not hold the gauge, but it WOULD feed the gauge from the mag well just like a round.

 

[chud]

Okay, Now the next question. Is it really not a good idea to use go/no go gauges on milisurp? Someone posted to use field gauge only. Of course I've read the opposite in books on milisurp.

 

[chasdev]

Go-no-go MUST be used when reaming a chamber such as when a barrel is replaced.
Field gauge is just that, to employed on a "used" barrel/receiver set up.
It tests for safety, period, although I have owned a Turk or two that failed and still shot fine....
I have however noted that my most accurate k98's also had the tightest headspace.

 

[chud]

Go-no-go MUST be used when reaming a chamber such as when a barrel is replaced.
Field gauge is just that, to employed on a "used" barrel/receiver set up.
It tests for safety, period, although I have owned a Turk or two that failed and still shot fine....
I have however noted that my most accurate k98's also had the tightest headspace.

So chasdev, Is it safe to use my go-no-go gauges or will it be a false test?

 

[zachary78]

If you have a no go guage, by all means give it a try. If the bolt won't close on the no go then your fine. If the bolt does close on the no go guage then you might want to call around and try to find a gunsmith with a field guage.

As far as safes go, mine is a cannon because they had the best warranty I could find. Even the cheapies they sell at wally world are better than nothing.

 

[zachary78]

One more thing: you want your chamber squeaky clean when you check headspace.

 

[creepiE]

Use a no go or field. Brownell's sells them pretty cheap.

 

[chud]

A big thank you to all your help. I do have brownells go-no-go gauges. They are worth the price. Why mess with home made.

 

[sgt rock]

From what ive read you remove the firing pin and extractor when using gauges to check headspace, this way nothing is interferring with the gauge to give you a false reading.Your checking the distance from the chamber shoulder to the bolt face and want a true measurement. Also these gauges are used to check headspace not used as a cartridge to see if the rounds are feeding correctly by the bolt .


http://rds.yahoo.com/_ylt=A0geu8tAo...spx/NS/General/DisplayPDF.aspx?f=bt002025.pdf

 

[sgt rock]

See above, but you don't have to remove ANYTHING.
You have to hold the bolt stop lever open as you install the bolt with the gauge held by the extractor claw and then the follower stops forward movement push down on it with a probe or screwdriver.
If your floorplate pops off without a struggle, do it that way.
If your extractor claw will not hold the gauge tight enough to keep it from falling out, then you may be able to feed the gauge into the mag and treat it as if it was a round holding the nose of it to the rear as you slide the bolt forward.
I found one yesterday that would not hold the gauge, but it WOULD feed the gauge from the mag well just like a round.

Why are you using a Headspace gauge as a cartridge for testing how rounds would feed ?? thats what dummy rounds are for.

 

[chud]

Why are you using a Headspace gauge as a cartridge for testing how rounds would feed ?? thats what dummy rounds are for.

Good question!

 

[tjg79]

I agree with sgt rock. The headspace gages should not be used for the purpose of dummy rounds.

The headspace gage is a precision measuring instrument. It needs to be handled and stored with care to avoid damage and ensure a long an useful life of accurate measurements.

The action of loading a headspace gage from the magazine could easily damage the chamber or gage and give a bad measurement indication.

Also, zachary78 brought up an important point that the chamber and bolt face need to be very clean.

The extractor and firing pin should be removed to avoid any interference and erroneous measurements. You do not want to close the bolt on a gage as if you were loading a round.

To avoid problems with the extractor collar getting stuck inside the rear receiver bridge with the extractor removed, either remove the collar or clamp it tight to the bolt with a piece of wire.

 

[MCQueenie]

Why are you using a Headspace gauge as a cartridge for testing how rounds would feed ?? thats what dummy rounds are for.

Just exactly where did he say he was doing that? What he said was he had a bolt with an extractor that wouldn't hold a gauge so he tried feeding it from the magazine and it worked that way.

 

[Heirmossy]

Chasdev has extensive knowledge on the K98. I do all my own headspace checks on my rifles and the only thing I do different is remove the extractor. My own preference. It's not necessary. He doesn't check "feed of the cartridge" with the gage. He uses the mag well and extractor when it's necessary to hold the gage in this fashion. This method performed carefully will not hurt the gage in any way. The gage is hardened and ground. I was a machinist for 20 years and have been in QA for the last 10. Many conditions arise in which a gage must be "fed" into a feature.

 

[Spitzenmeister]

A big thank you to all your help. I do have brownells go-no-go gauges. They are worth the price. Why mess with home made.

Indeed.

 

[sgt rock]

Just exactly where did he say he was doing that? What he said was he had a bolt with an extractor that wouldn't hold a gauge so he tried feeding it from the magazine and it worked that way.

Your right my appologies,after i read it again the server wouldnt let me change it or log on to the boards , i still puzzles me as you dont want the extractor interferring with the measurement . To each his own.

 

[chud]

So.... In retrospect I perform the treatment like the Mosin Nagant. Enough said. Thanks