.300WM Bullet & Powder Combo Load Help

[wombat13]

I'm just getting into reloading for my .300WM. I've got the Sierra 2nd Ed. manual from my FIL and I've gone to the powder and bullet manufacturers websites, but I'm concerned that I may not have all of the appropriate min and max load data that I need given the bullets and powder I purchased.

Here are the components I have:

Powder: IMR 4831 and Reloader 22
Bullets (all 180 gr.): Nosler Ballistic Tip, Hornady SST, and Sierra Gameking
Brass: Winchester
Primers: Winchester Magnum Rifle

I bought these components after reading THR and other sites - these seem to be some of the most popular bullets and powders for .300WM.

Here is the load data I have:

Sierra Manual 2nd Ed.
For 180 gr. spitzer boat tail: IMR 4831, Start 67.3, Max 74.6

IMR Website: 180 gr. SPR MT-SP, IMR 4831, Start 69.0, Max 74.0C

Nosler Website: 180 gr. Ballistic Tip, RL-22, Three loads listed - 71.5, 73.5, and 75.5.

Here are my questions:

Do the loads in the Nosler website represent the min to max range? The velocity they list for the 71.5 gr load is 2928 fps. This seems too high for a min or a starting load. What charge of RL-22 should I start with?

Can I interchange these bullets with the load data that I have? The Sierra manual data clearly applies to the SGKs, but can I use that data for the SSTs and the Nosler Ballistic Tips? Can I use the SGKs and SSTs with the Nosler loads?

If the data I have is insufficient, I would appreciate any data that you all can offer for the bullets and powder that I have.

Thanks.

 

[Captcurt]

None of them are the same.

I own 7 loading manuals and none of them have the same starting and max loads. Always start at the min. load no matter which book you use.

I compare several books before I start. If most of them show starting load within a grain or two that is where I start. We're talking rifles here. Some pistol loads only vary 2 gr. from min to max.

 

[Greg Mercurio]

Don't ignore IMR 4350. It works very very well for me.

 

[Grumulkin]

Your components aren't used in this load but it's what worked the best for me.

The most important part of information is the starting load. Compare data and go conservative. Regarding the maximum load, be guided by both the manuals and by pressure signs. Generally, when starting low, the groups will tighten to a point and will then start widening. Stop where the groups are tightest and the pressures will generally be fine. This, of course, applies to guns with strong actions and not to lever actions, pumps and semi-autos. Also look at such things as primers.

In a number of cartridges, I can find examples of where the maximum load listed in one manual is the starting load in another. I think it's about as important to know when the pressure is low as when it's high. Look down the barrel after you shoot. If there is a lot of residue, it's a light load. If the primer is pushed out of the pocket, it's a light load (yea, really); this is different than a blown primer. If there is soot around the neck and body of the case, it probably a light load.

I routinely switch bullets of the same weights in my loads. Occasionally you'll need to adjust the powder charge a little bit either way for optimal results but most of the time you don't need to make any changes at all.

 

[NCsmitty]

www.alliantpowder.com lists their Rel-17, Rel-19, Rel-22 and Rel-25 for use with 180gr Speers, and the max loads show under 25 fps spread between all 4 powders, in the 300 Win Mag.
Start loads are a 10% reduction of the maximum loadings listed, according to Alliant's recommendations.

I'm a firm believer in using manufacturer's/distributor's data that's listed online, as it is the latest, up to date information available. I use my manuals to cross reference to the online data, not the other way around.



NCsmitty

 

[wombat13]

I routinely switch bullets of the same weights in my loads. [/B] Occasionally you'll need to adjust the powder charge a little bit either way for optimal results but most of the time you don't need to make any changes at all.

That's exactly what I wanted to know. Another thread on THR discussed the different shapes of bullets and how they affected pressure, so I wasn't confident that I could use the same starting loads for my different bullets.

Also, thanks for the info on spotting signs of light loads.

 

[wombat13]

www.alliantpowder.com lists their Rel-17, Rel-19, Rel-22 and Rel-25 for use with 180gr Speers, and the max loads show under 25 fps spread between all 4 powders, in the 300 Win Mag.
Start loads are a 10% reduction of the maximum loadings listed, according to Alliant's recommendations.

I'm a firm believer in using manufacturer's/distributor's data that's listed online, as it is the latest, up to date information available. I use my manuals to cross reference to the online data, not the other way around.



NCsmitty

Thanks for the info. It wasn't clear to me that the loads on Alliant's website were the max loads. I'll start with 69.5 gr of RL-22 and proceed from there.