OAL for Xtreme 124gr HP

B

Bosn Ski

New member
According to Alliant's data for BE-86 the OAL for a 9mm 124gr JHP and FMJ is 1.12. Most of the data I've seen has HP OAL in the 1.06 range.

I am thrown off by the same OAL for JHP and FMJ.

I am working up loads for the 124gr HP at 5.0, 5.3 and 5.5. At 1.12 the bullet seems like it is barely in the case. It plunks fine in my barrel and mags.

Can I set the Xtreme 124gr HP a little deeper?
 
Be aware that for the same bullet and charge a shorter OAL means less case volume and therefore higher pressure. A longer OAL means lower pressure. If you are near the minimum load, then go ahead and use a shorter OAL, but if you are close to maximum be careful. You also need to be careful not to shorten it so much that you compress the powder. Some powders in some calibers don't like to be compressed.

The OALs in load manuals are not cast in stone, but you do need to be careful.
 
OAL is always Bullet and firearm specific, never manual specific. Find the OAL that works best in YOUR pistol. Then start low and work up.
 
I have loaded Xtreme 124gr CPHP's at 1.09" COL, which I think is still a but long. Now I am planning on working up loads at a 1.060" COL, but I am starting at the MIN load again. I have not loaded BE-86 yet, so I cannot comment on your starting charge.

Be safe.
 
I have loaded Xtreme 124gr CPHP's at 1.09" COL, which I think is still a but long
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And I load my Precision Delta 147gr FMJ-TC at 1.135. Now, it has to be longer to accommodate the heavier and therefore longer bullet, but the minimum OAL without compressing the powder is 1.095 or thereabouts. I've read other posts where it's clear that people are using the longest OAL they can. You seem to want them as short as you can (my perception from one little sentence, I admit).

So my question, is there a general consensus for either long or short? Not what's best, but what people prefer for whatever reason.
 
You seem to want them as short as you can (my perception from one little sentence, I admit)
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Chasing the COL has always been difficult for me. For 40S&W I have been loading at 1.142", which is over the SAAMI MAX of 1.136" and it seemed to work for my SIG guns.

For 9mm 124gr, I have been loading the Xtreme RN at 1.150" and the Xtreme HP at 1.090". The 1.090" was calculated based on the difference in length between the RN and HP. What I have found with my COL's were that my loads are always close to the MAX or over. The MIN loads always felt very weak. In some cases I had good groupings but POI was high due to low pressure, so I started lowering my COL to bring up the POI. I could also see when the bullets are loaded, that I could definitely see some of the trunk/body of the bullet above the mouth.

Since I was loading some new bullet/powder combinations, I decided to bring the COL down a bit and see how these loads work out pressure and accuracy wise.

Every caliber is different when it comes to chasing the COL. For 357sig it is actually easier since your COL range is about 1.135" to 1.140", with the bullet shape dictating what you can load.

**edit**
Please be careful and do your homework if you are planning on loading to a lower COL than the Alliant recommended MIN COL of 1.12" for 124gr JHP.
 
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