New to reloading Have qustion on OAL

[kevinm]

Thanks for looking .
My qustion is why don't you use the max oal ?
Like on 9mm the max oal is 1.169 and in the reloading book 115 fmj is 1.10 what will happen if i go out to 1.159 ? thanks and hope this makes sence.

 

[50 Shooter]

First would be, will the 115gr still fit into the case if seated out to the max OAL. 2nd, would there be enough in the case to get a good crimp on the bullet. 3rd, if you could seat it that long is it going to sit straight enough in the case also to be accurate. 4th, if you seat it out that long will it still fit into your magazine when you load it.

These are the other questions you need to ask yourself when loading any ammo out to max lengths.

 

[something vague]

Accuracy, complete powder burn, and most of all magazines. Think the dude above hit it on the head.

 

[kevinm]

I love this Forum . thanks for all the info .

 

[rcmodel]

Even more important is the shape of the lighter bullet. Or just the shape of the bullet period. Say a 115 RN-FMJ vis a 115 JHP?

A short squat JHP bullet seated to max 9mm SAAMI OAL would very likely be jammed tightly into the rifling before it could chamber fully.
It would fit in the magazine, thats all the SAAMI max spec is concerned about.
But it might not fit in the chamber.

Also, there is way less full diameter bearing surface to get proper neck tension and prevent bullet set-back.

rcmodel

 

[DT Willy]

I'll respectfully throw in another opinion on the OAL question. Richard Lee, in "Modern Reloading" warns of the danger of approaching minimum OAL because of the possible high pressure associated with reduced case capacity. He also states that "BEST ACCURACY is usually obtained with bullets seated at the MAXIMUM overall length and crimped." While I don't load my 9mm to 1.169", I have found that OAL's on the longer size (i.e., 1.14-1.5") do support Mr. Lee's statement and give me some darn accurate ammo. Experiment and see what works for you. This is one of the pleasures of reloading. Best, DT Willy

 

[Uncle Chan]

For my automatics, I seat them just far enough to reliably feed from the magazine. For the .223, I seat to 2.10. Not a 9mm, fer sure, but you get the point. I don't matter to me what the specs on the cartridge say, if it don't fit in the magazine, it is too long. 2.10 is just right for my Mini-14.