Shoulder bump

[Richard Slaton]

When you bump your should do you bump just enough that the bolt will close or bump enough that bolt just starts to close feel no resistance from the brass. At RB I shoot a clunker Savage so I don’t know what smooth bolt closes feel like lol. Barry between you and me Mr.Wynne may to buy larger data plan for this site
Luckily you post stuff to make people winners My post will just make you just average

[Barry Holcomb]

I’m almost embarrassed to say it, but I didn’t own a set of headspace gauges until a few months ago. Lol. I just always took a fired case, sized it in my die, tried to chamber it and if it needed more I’d adjust the die down a little further until it wasn’t hard to close. I also would pull the firing pin assembly and check resistance on closing the bolt after I sized to what I thought it should be. With all of that being said, just go on Amazon and order a headspace gauge kit with the comparator and be done with it. Mr. Richard, I agree a savage (which is no clunker)is much tougher to do that with and my bighorn action is very similar and having the comparator let’s me know for sure. There are many differing opinions on amount of shoulder bump and probably anywhere between 1-3 thou will work great.

[brett collins]

mr richard i size my brass to give me.0015 Clarence. back in the day i went for.002 but since I have learned how to be consistent with the pressure, I put on my press .0015 is obtainable.and i feel like that helps with brass life. and i also believe that annealing every cycle helps even more.

[brett collins]

richard at .0015 there’s only the slightest hint of resistance and that’s only because the chamber starts getting a little dirty after firing 60+ rounds

[tyler]

I bump a lot. Like, enough to feed in an auto loader really easily. That one that the bolt closes a little bit funny on is going to go somewhere different than the rest of them. I make sure than none of mine close funny. That is from my gunsmith mentor buddy and it’s done well for me so far.

If your chamber is getting dirty, that’s something I would address. The shoulder should seal against the chamber before any gas can blow back. Certain powder and brass combinations can cause soot to blow back and your trigger to fail mid match… unless it’s a triggertech… ask me how I know.

[brett collins]

TYLER blowback is not the only reason why a chamber can get dirty simply opening the bolt and extracting a case will deposit a small amount of carbon into the chamber and after time there will likely be a small amount left in the chamber even if you are getting good combustion with a clean burning powder it doesn’t take much with only.0015 Clarence

[tyler]

I would recommend more clearance, if that’s the case. My chamber doesn’t get dirty that I can tell, so I’m not sure I’m following. That’s not the reason I bump a lot, anyways. If it works for you, awesome. It might bite you one day when you get that weird flyer at the end of your 3rd string when that bolt closes a little funny. My bolt drops closed on a closed case when I pull the firing pin.

I assume you’re pulling the barrel and using a depth mic to measure a fired and resized case to get the 0.0015 number? My electronic mitutoyos and dial starrett doesn’t give me good enough resolution for my tastes.

[tyler]

Sized, not closed case. Mistype.

[Ron Williams]

As little as possible less than 1 thou enough I can close the bolt with slight pressure with the fp and ejector removed.

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