.451 HSM HP below min. oal

[Cump]

I'm trying to load some .451 HP bullets made by HSM. Over 4.6 grains of Bullseye for my 1911. I set out for 1.23 oal, but it failed the plunk test, so I seated further until it marginally passed.

The bullets have pretty round shoulders and in order to fully chamber have to have an oal under the minimum = 1.16 inch.

Do you think that raises pressure to an unsafe level? Unless someone has experience that it is acceptable, I will pull the bullets.

Also, do you think these particular HSM bullets are just not right for my chamber, or am I missing something?

Thanks for the help.

 

[rcmodel]

What is the bullet weight?

rc

 

[LiveLife]

Above is a comparison picture of PMC and CCI/Speer factory rounds and Berry's/HSM rounds. I have to seat the 230 gr HSM HP down to 1.147" to pass the barrel drop "plunk" test in my Sig 1911 barrel. If you compare HSM HP to Berry's RN and imagine a nose tip on top of the HP, bullet shoulder near the case mouth looks similar.

If you are using the 230 gr HSM HP, I think the bullet base is longer and gets seated deeper than what Lyman #49 lists for 225 gr Speer JHP at 1.243":

225 gr Speer JHP Bullseye OAL 1.243" Start 3.1 gr (554 fps) 7,100 CUP - Max 5.3 gr (840 fps) 17,400 CUP

Since HSM HP is a plated bullet, I would start with conservative start charge. I used W231/HP-38 instead of Bullseye for reduced recoil pulse at higher charges.

Personally, I would not start at 4.6 gr at 1.160" and would pull the bullets. If I used 1.147" and Bullseye, I would initially test 3.2, 3.4, 3.6, 3.8, 4.0 and see how things go. If you want another reference, 2004 Alliant load data lists following for 230 gr Lead bullet and Bullseye for a target load - http://www.thehighroad.org/attachment.php?attachmentid=182147&d=1364769070

230 gr Lead Bullseye OAL 1.190" Max 4.0 gr (810 fps) 13,900 PSI

 

[Cump]

It is 230 gr. Thanks for the info. I will pull them and try a lighter load with the short oal.