OAL of 9mm 125gr HP bullet

[trapper9260]

Hi I like to have some help on the OAL of 9mm lyman 125gr HP cast bullet . The manuel says the OAL is 1.010 and with the powder you can not get it to the OAL I can only get it to 1.030 . could the manuel have a mistake on the OAL . Or is there something I am doing worng .I got this info out of the new Lyman cast manuel . I have use the same manuel for the 120gr and the 147 gr and no problem .
Thank you

[marvelshooter]

Does it feed? Does it chamber? If so shoot it. I don't get too excited about attaining a particular OAL because there are too many variables too contend with like how deep is the chamber cut. When I am loading a new bullet for either a 9mm or a .45 I pull the barrel and seat the bullet until the back of the case is just below flush with the back of the barrel. I then record this OAL for this bullet in this gun.

[MtGun44]

The only value of the OAL is to have an idea of where the base of their boolit was in the
case when they were doing pressure testing. If your base is deeper, you should back off
the powder charge a bit. If it is higher, then you will be OK.

The throat shape and length in the barrel, the magazine size and feeding requirements will
set the actual OAL that you use.

Bill

[trapper9260]

Does it feed? Does it chamber? If so shoot it. I don't get too excited about attaining a particular OAL because there are too many variables too contend with like how deep is the chamber cut. When I am loading a new bullet for either a 9mm or a .45 I pull the barrel and seat the bullet until the back of the case is just below flush with the back of the barrel. I then record this OAL for this bullet in this gun.

lets say that the cast bullets that I load already that are 120gr and 147gr what the OAL of them works just use that then to make it easyer for me to know what will work then . Just a idea and pick your mind
Thank you

[williamwaco]

I suggest that you put the caliper away and forget about COL.

You don't really care how long the cartridge is, all you care about is that it feeds and locks into battery reliably.

At some point it will not feed. That is too short.

At some point the front driving band will engage the rifling too hard and the slide will not close reliably. That is too long.

Field strip your pistol and use the barrel as a gage. Start with a bullet seated with most of the driving band out of the mouth. It will not slide into the chamber completely under its own weight. This is too long.

Now screw the seating die stem in one half turn at a time and re-try that bullet in your chamber until the cartridge falls easily and fully into the chamber under its own weight ( do not push it ). ( I do this with an unprimed and uncharged case.)

Now lock the seating stem, load about two mags full and see if they feed reliably. If they do, you are finished. Take the empty unprimed cartridge you used as a gage and store it in your die box with the dies and use it in the future for adjusting the die after you have changed it for another bullet.


Next, refer to:

http://castboolits.gunloads.com/showthread.php?t=136526


for significantly more detail.



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