458 SOCOM load data

[Sgt_Jamez]

I've been scrubbing Google for all relevant load data on the SOCOM and there doesn't seem to be a lot out there. I find a lot of links to dead sites and such.

I've also noticed that there is a wide variance to COAL. Can someone tell me why this is not a case of "load to mag length"? I bought some factory COR-BON ammo and it is way short of mag length, so I am confused on how to arrive at a proper OAL when there is very spotty load data.

Can anyone help?

Specifically I need OAL for the following slugs:

Hornady Interlock 300gr HP
Hornady FTX 325gr
Speer Hot-Cor 350gr FN
Hornady 405gr RN
Barnes Banded Solid 500gr

Just the OAL would be a huge help, but even better if someone could tell me how one can arrive at a proper OAL when little published load data exists. Thanks for reading!!

 

[penumbra]

Re: 458 SOCOM load data

motherlode of info on the 458 SOCOM is at:

http://www.teppojutsu.com

check the forum!

 

[Grumulkin]

Re: 458 SOCOM load data

There are several things you need to know about COAL:

1. If the bullet is seated deeper the pressure increases and if seated further out pressure decreases unless the bullet is so far out that it contacts the lands in which case pressure increases.

2. If you wish to crimp (I don't for the 458 SOCOM), then seat to the cannelure and/or crimp with a Lee Factory Crimp die.

3. In general, with some exceptions, seat so at least 1 caliber length of bullet is within the neck of the case.

4. Seat so the cartridges feed dependably through the magazine if the gun has a magazine.

5. Seat so the bullet is as near the lands as possible without actually touching them.

After doing the above, it's your job to evaluate pressure signs to be sure the loads are safe. In the 458 SOCOM in an AR-15 platform, pressure getting up toward maximum is indicated by scuff marks from the chamber on ejected cases.

 

[Sgt_Jamez]

Re: 458 SOCOM load data

Pen - I haven't found tons of data at that site. Would you be more specific as to where on Marty's site the motherload is? I hope I didn't miss it but I didn't find any real reloading data there.

I did join www.beyond556.com though.

 

[Sgt_Jamez]

Re: 458 SOCOM load data

Grum -

1. I understand that bullet seating depth is tied to case capacity and in turn case pressure. So that's why I am trying hard to make sure before I press out a single round I have the correct data.

3. For the SOCOM, would the 1-caliber seating depth be a general starting point? I assume I should not seat shallower than that depth. Is there a way to determine if I need to seat even deeper? What would be the exceptions to this rule?

 

[Grumulkin]

Re: 458 SOCOM load data

The 1 caliber seating depth would be a general starting point and yes, there are exceptions. One exception would be the 300 Winchester Magnum where the neck itself is less than 1 caliber long so with that cartridge you'll always have less than 1 caliber of case gripping the bullet.

Another exception is with heavier bullets; notice I said 'at least' one caliber seating depth. If, for instance, you're loading 220 gr. bullets for a 30/06, unless the gun has a really long throat and a long magazine, you'll have to seat bullets with the base well below the neck.

In regards to the 458 SOCOM in particular, there would be heavy bullets where you would have to load with the bullet base below the neck. That would happen with 500 gr. bullets. I have never loaded 500 gr. bullets in mine so can give no personal loads for that bullet. Also, I believe some 458 SOCOM loads were worked up with guns other than the AR-15 platform in which case with 500 gr. bullets, the bullets could have been seated much further out than would have been possible with an AR-15. You have to know how the data was generated to know the general seating depth to use and if deeper seating would be safe.

The teppojutso.com site is an excellent source of 458 SOCOM information. I do have a bunch of 458 SOCOM load data most of which hasn't been tested by me. If you PM me your e-mail address, I'll be happy to send it on to you.

 

[BIGFATJEF]

I contacted the developer and they sent the attached.

Cheers

 

[BIGFATJEF]

I've been scrubbing Google for all relevant load data on the SOCOM and there doesn't seem to be a lot out there. I find a lot of links to dead sites and such.

I've also noticed that there is a wide variance to COAL. Can someone tell me why this is not a case of "load to mag length"? I bought some factory COR-BON ammo and it is way short of mag length, so I am confused on how to arrive at a proper OAL when there is very spotty load data.

Can anyone help?

Specifically I need OAL for the following slugs:

Hornady Interlock 300gr HP
Hornady FTX 325gr
Speer Hot-Cor 350gr FN
Hornady 405gr RN
Barnes Banded Solid 500gr

Just the OAL would be a huge help, but even better if someone could tell me how one can arrive at a proper OAL when little published load data exists. Thanks for reading!!

Lyman 50th edition page 351 shows oal at 2.145 to 2.245