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Harpman
01-13-2006, 10:52 PM
In my turk 38, primers are backing out just a tad, same load in 98/22 do not do this, would this be a headspace issue ?...if so, Is there a way to check without buying a gauge ?....or is that too dangerous to try ? no other signs of any kind, just slightly backed out primers. also I know the spring is weak, have one coming in mail...I do have a metal lathe, if I had the specs, I could probly make a gauge.

45 2.1
01-13-2006, 11:45 PM
I don't think there is a practical way without a gauge, but the good news is you can form 8mm cases from 30-06 a set the correct headspace for that rifle where that doesn't happen.

waksupi
01-13-2006, 11:52 PM
Harpman, do you have all the oil removed from your chamber?

Harpman
01-14-2006, 12:10 AM
I will double check the oil , I think its pretty much cleaned 100 percent, I just totally refurbed this one down to bare metal, not a dang spec of anything inside or out., I dont understand about the reforming brass, I have plenty of 8mm. If I resize 06 it will be the same as my 8mm, I have now, both run through the same sizing die and all....I did do a partial resizing with the full lenght sizing die and that seems to help some. maybe just necksizing will do it.

NVcurmudgeon
01-14-2006, 12:11 AM
Without headspace or cartridge case gauges you can get a rough idea of headspace with factory cartridges and shims. Better yet, as 45 2.1 posted, form cases from .30/06, or expand 8 X 57 cases to .338 or .35 caliber, then reduce the neck diameter to 8 x 57, progressively deeper, until the bolt will just close with a crush fit on the newly formed case. Then neck-size and don't worry about headspace.

waksupi
01-14-2006, 12:40 AM
curmudgeon has a good point. Take some of the cartridges you fired, don't size, and load a light case forming load in them, bullet seated out to contact the lands. Fire them off, and you have the proper size brass. Headspace fixed. Just don't FL resize them afterwards, just neck size, and bump back the shoulder whenever they get hard to chamber

762cavalier
01-14-2006, 07:51 PM
curmudgeon has a good point. Take some of the cartridges you fired, don't size, and load a light case forming load in them, bullet seated out to contact the lands. Fire them off, and you have the proper size brass. Headspace fixed. Just don't FL resize them afterwards, just neck size, and bump back the shoulder whenever they get hard to chamber
How does one "bump back the shoulder" without using a full length sizing die thereby defeating the purpose of fireforming. would like to do this with an arisaka that I have . :)

Ricochet
01-14-2006, 09:10 PM
How does one "bump back the shoulder" without using a full length sizing die thereby defeating the purpose of fireforming. would like to do this with an arisaka that I have . :)
I think that Ric meant to use a full length resizing die to "bump back the shoulder" just enough to let the cases easily chamber in that rifle when they get tight after firing several times with the neck sizing only.

762cavalier
01-14-2006, 09:27 PM
OH Is that accomplished by screwing the die out a little bit. I think I get it but not sure :???: If that is the case is there a way to determine how far out the die shoud be screwed. Thanks for the help

waksupi
01-14-2006, 09:58 PM
OH Is that accomplished by screwing the die out a little bit. I think I get it but not sure :???: If that is the case is there a way to determine how far out the die shoud be screwed. Thanks for the help

Once you have the case length obtained, screw your die down to contact the shoulder of the newly fireformed cases. Then they will remain chamber size. You would only have to bump back the shoulder, if you only partially resize each time your load. I generally just size about 1/3 of the neck, so the shoulder will come forward a bit after several firings. When that happens, the die is screwed in enough to give easy chambering again. You will know when it is time to bump back the shoulder, when you begin to feel resistance when closing the bolt, and turning the handle down into position.

762cavalier
01-15-2006, 01:25 AM
Thank you Sir I think I finally get it not too terribly difficult.

mag_01
01-18-2006, 12:39 AM
:lovebooli ---- Just a word about headspace----You should be able to find out on line what the headspace specs. are for ur rifle---- roughfly 3 levels----primers back out---primers are driven back in and things look ok---cases seperating---this last one is the worst---starts by showing a ring about 3/8ths. up from base--The Gun I worked on was a SMLE---303--british most cases fired would show signs of case seperation-- head space for this rifle was about 5 ths.--and a field type max gauge of about 7 ths.---sry dont have info. in front of me---with rough - measurements i found it to be about 15 to 17 ths.----u could make shims and get a better reading---- I solved my headspace problem by welding the back of the lugs and then refitting it to rifle---when I close down on a case now that last little bit of bolt travel snugs up behind case head---headspace also affects accuracy---I no longer have split cases or a dreaded headspace prob. ---hope this info will be of some help----just what I was through getting this Mil Surp to shoot--------Mag :castmine: