Over all length question...

[HAWKEYE10]

I made a jig to measure the OAL for my rifle only. I have a Savage M12 with a single shot adapter in .223. I am going to use a Hornady 53 grain HP item # 2250. The Hornady book gives the OAL at 2.230 and my measurement is 2.250. I think I need to back out ten thousands to get the bullet off the lands. OK that leaves ten thousands and that is not much. My question is am I wasting my time and at my age much needed energy worrying about this? Don

 

[Rule3]

I made a jig to measure the OAL for my rifle only. I have a Savage M12 with a single shot adapter in .223. I am going to use a Hornady 53 grain HP item # 2250. The Hornady book gives the OAL at 2.230 and my measurement is 2.250. I think I need to back out ten thousands to get the bullet off the lands. OK that leaves ten thousands and that is not much. My question is am I wasting my time and at my age much needed energy worrying about this? Don

IMHO, yes I have basically the same rifle M12 VLP DBM. I use Hornady brass and bullets. Brass trimmed to 1.750 (as theirs is) I just use the OAL listed in the manual. I have been using the #2267 55 gr bullet with w/c. It's a tack driver. All mine fit in the detachable box magazine. It shoots better than I can from a Tack Driver sand bag.

 

[jdayer]

Hmmmm, over all length varies from rifle to rifle quite a bit. The distance from shoulder to rim varies less. You could make a fixture to measure the shoulder to rim length or you could cast the chamber to find out where the rifiling starts or you could try oversizing the neck slightly with a custom made spindle so that it opens the cartridge neck up slightly after sizing. Then you can shove a bullet that slips in the neck, chamber the round and measure the cartridge overall. I would probably use bluing on the bullet to make sure you hit the rifiling. This is a big deal in bench resting and I have heard lots of stories about how to do it. The distance from the bullet to the rifiling is a big deal for accuracy and lots of shooters play with that to improve accuracy. Most tell me the bullet should be no more than about 0.005" from the rifiling, less is better. One guy advocated making bullets the longest you could and still chamber them. Make the cartidge long, see if it fits, keep going until it doesn't and then back off a bit.

 

[Rule3]

True bench rest shooter are very precise/anal/OCD whatever. You can get a Hornady gauge, smoke/sharpie the bullet and test and fiddle until it drives you nuts. Have you tired just the suggested lengths and loads?

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