Headspace/kopspasie - goeie leestof

[Lategan1]

Ek deel graag, mooi verduidelik. Ook vir Ackley.

Met komplimente.

https://www.sportingshooter.com.au/news ... e-shooting

Beste.

[Lategan1]

Komplimente van Calguns.net.

Bolt lug set back and headspace.

Bolt lug set back is caused when cartridges that generate too much pressure and bolt thrust cause the bolt lugs to form indentations into the lug recesses in the receiver. The type of firearm that is usually most susceptible to this are small ring Mausers that have been converted to calibers that are too powerful for the action. It can also be caused by unsafe, heavy charges in handloads.
The symptoms of bolt lug setback are shiny depressions in the face of the lug recesses that are typically pushed back around .004" You need to remove the barrel to inspect this area of the receiver. Sometimes, if you gently pull back on the bolt handle as you close the bolt on an empty chamber you can feel the bolt lugs fall into these depressions.
Bolt lug set back causes excessive headspace in the weapon. The sidewalls of the cartridge case can stretch near the head area, and if reloaded might cause a case head separation. A case head separation can destroy even a very strong weapon. Because of the lack of gas handling features on a small ring Mauser, a case head separation could be especially catastrophic with this type of rifle.
The way to fix bolt lug set back is to grind the bolt lug recesses on the inside of the receiver flush again. Do not try to machine them because the set back will have caused work hardening, and the recesses would present an interrupted cut. This will virtually guarantee chatter and an uneven surface with a boring bar. Then the receiver will need to be heat treated again, (the grinding will have removed the case hardening from the face of the recesses). Because the grinding operation will cause the bolt to sit back farther in the receiver, the root of the bolt handle may need to be built up with weld and reconfigured so that it will mate properly with the extraction cam surface. Then the barrel will need to set back, and rechambered.
It is almost always the case that a rifle with bolt lug set back is not economically worth fixing. However, if left with the set back, it is dangerous to operate. Because this problem is usually found on small ring Mausers that have been converted to 7.62 NATO, and are being fired with 308 Winchester (which is higher pressure), I'd recommend that if you are using this type of rifle, that you replace the receiver. Right now Sarco is selling model 1893 Mauser receivers for $20 each. the bolt from either an 1893, '94, or '95 will work in these receivers. (a Swedish 1896 bolt will not) This would be the cheapest fix available. Remember to always check the headspace whenever you swap major components on an action.

[Ralph Badenhorst]

Skiet Small Rifle primer doppe - hulle kan meer druk vat......................................................

My vraag gewoonlik is - kan die aksie dit vat.............

Maar wat weet ek

[moemin]

Baie dankie, nou het ek iets om vanaand te loop lees

[Lategan1]

Wanneer jou vollengte matrys, nadat dit korrek opgestel is, jou doppe te veel verklein vir ‘n geweer met ‘n groot kamer en moontlik ook laat met ‘n “headspace” probleem. Met komplimente vanaf die Redding webblad, sien vir volledige artikel.

“To check for excessive case sizing, compare the dimensions of a fired case and one that has been resized. The diameter of the fired case at any point should not be reduced more than 0.005". If you find that your cases are being sized more than this, an oversize chamber or undersize die may be the problem. Sometimes, it may be possible to polish or hone the die to better match the chamber. Check with the factory if you suspect this problem.”

Beste.