OAL Question

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I was trying to find the length of the chamber on my m44. The loading books say OAL should be 2.75 min. When I try to chamber a round @ 2.75 I really have to smack it to get it to lock up. I started to mess with the OAL using a snug fitting bullet in a empty case. It turns out that for this particular bullet my rifle likes 2.70 oal. Anything wrong with my thinking? Basically I just adjusted the bullet until the bolt closed with just a bit of a push.
Seems like depending on the ogive of the bullet the OAL will vary. My only concern is to short an OAL creating an over pressure problem. The PPU rounds are over three inches long. Can the OAL vary that much?

thanks

[mogunner]

On rifle rounds, your OAL won't affect pressure nearly as much as pistol rounds do just due to the burn rate of powders used in rifle versus pistol loads. My Lyman doesn't list a minimum, just a recommended at 2.8-ish depending on bullet used. Unless you're pushing the ragged edge of max load chasing velocity, you can decrease the OAL that much easily.

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Thanks. I was hoping that. Last reloading session I used the load data to set the OAL. Real tight and hard to chamber. With this shorter AOL they chamber slick as snot. I'll see if the accuracy improves.

thanks again for the help

[entropy]

OAL (or as I prefer COAL) in rifles usually uses the index of fitting into the magazine more than filling up the free bore. When you start fiddling with such things, you are shooting in a class way above most Mosin Nagants in accuracy. It's not worth seating to max freebore in about 99.999999999% of Mosins.

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Thanks. What started this was the fact the with the book coal (your right) my rifle was hard to close the bolt. When I shortened the coal the bolt closed like it should with just a bit of push on the bolt. Since I was there anyway I started fiddling with finding the proper coal for this rifle. I am having a problem with accuracy. This is an m44 built in 1947 and appears to have very little use. Its not shot out. I just haven't found the load it likes as of yet. Thought this may help in the process. I was shooting PPU and it was very hard to close the bolt. My loads, with the book coal, were still difficult to close the bolt. Shorting the coal is a huge difference in chambering a round. Maybe it will help just a bit in accuracy. I know it won't make much difference but it's just a piece of the puzzle.

[bunkysdad]

If you have a round nose soft point heavy bullet it can change the oal compared to a pointed fmj. Just depends on where the shoulder of the cartridge make contact.

[silverado1999]

If you don't have one already, buy a copy of Modern Reloading 2nd Edition, by Richard Lee. He lists the Minimum OAL for each load. Maybe this info would help. Just a thought.

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Thanks guys Have been away and not able to work with the m44. Will be starting again soon. I would really like to find a load that is accurate and not punishing. At least that is the goal.