338 lapua Hornady 285 vs HSM 300

[WCPORTING]

Question:

Im reloading and using Hornady 285 grain bullets for my 338 Lapua. The factory spec calls for a max OAL 3.625" .

OK, i have some HSM 300 grain bullets and the factory OAL is 3.680" .

Both the Hornady 285 and HSM 300 (bullets only) are the exact same length 1.730" with the HSM weighning 15 grains more.

Hornady OAL 3.625"
HSM OAL 3.680"

.055" difference

Would it hurt to set the OAL of the HSM 300 to the Hornady specs of 3.625"?
And if i do, will i have to run less powder.

 

[ChrisGarrett]

Re: 338 lapua Hornady 285 vs HSM 300

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WCPORTING</div><div class="ubbcode-body">Question:

Im reloading and using Hornady 285 grain bullets for my 338 Lapua. The factory spec calls for a max OAL 3.625" .

OK, i have some HSM 300 grain bullets and the factory OAL is 3.680" .

Both the Hornady 285 and HSM 300 (bullets only) are the exact same length 1.730" with the HSM weighning 15 grains more.

Hornady OAL 3.625"
HSM OAL 3.680"

.055" difference

Would it hurt to set the OAL of the HSM 300 to the Hornady specs of 3.625"?
And if i do, will i have to run less powder. </div></div>

First of all, who's making the 300gr bullet...Sierra, Berger, Lapua, Hunting Shack?

I wouldn't want to jam that 300gr bullet, nor the 285gr bullet for that matter, into the case anymore than I would have to, but that's just a personal preference in loading closer to the lands, while still being mag safe.

Also, by loading that 300gr bullet deeper into the case, you WILL increase pressure, maybe not a lot, but yeah...that's probably not a good idea unless you can cross reference that depth to other data, where it's shown as safe. I don't load the 300s, so I don't have those numbers handy.

What is the longest you can load a cartridge (COAL) and still fit your magazine?

That's what I would load all of my bullets to, unless I wanted to single feed them, like I did with the Berger 250 Hybrid test bullets this past week.

Loaded some mag length, but most were loaded long and I had to feed them one by one, which wasn't too bad, but it also allowed me to perhaps get a bit more powder into the case (or, in the least, not compress it) and get closer to the lands.

Chris

 

[WCPORTING]

Re: 338 lapua Hornady 285 vs HSM 300

Chris,
HSM 300 grain bullets. My Savage would not shoot these (misfire) so i pulled the bullets out of the cases, trimmed and reloaded the cases using the 300 HSM bullets i pulled out.
The factory cases were too long for the Savage.

 

[WCPORTING]

Re: 338 lapua Hornady 285 vs HSM 300

OK, thought it would safer to just max them out to 3.680" were they need to be. Reloaded and ready to test.

 

[ChrisGarrett]

Re: 338 lapua Hornady 285 vs HSM 300

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: WCPORTING</div><div class="ubbcode-body">Chris,
HSM 300 grain bullets. My Savage would not shoot these (misfire) so i pulled the bullets out of the cases, trimmed and reloaded the cases using the 300 HSM bullets i pulled out.
The factory cases were too long for the Savage. </div></div>

Just an FYI, the HSM 300gr bullets are the 300gr Sierra Match Kings.

Seems that they offer a 3.600" 300gr loading, your 3.680" loading and finally a 3.760" COAL for either single feeders, or guys with longer mag boxes.

I guess you would be safe when loading your 300s up a bit shorter, to 3.600", if you wanted to.

For reference, I loaded some of the Berger to a COAL of 3.848", which I figure is about .020"-.025" off the lands in my 6 yr old Sako TRG-42.

They actually didn't shoot quite as well as the batches seated a bit deeper and jumping more, which is odd for a couple of reasons.

Chris

 

[WCPORTING]

Re: 338 lapua Hornady 285 vs HSM 300

I appreciate the reply Chris, thanks for the info.