H4350 load work up.

[Rmitch223]

I've developed a fairly accurate load with my rifle using IMR-4350 and the 105 Amax in my .243 Win.

I'm switching to H4350 because of less temperature sensitivity.


I found two pounds of H4350 yesterday locally. So im starting a new load work up.

What charge weight do you recommend I start my workup at?

My Hornady manual shows a starting charge weight of 38.3gn and a max of 41gn.

Hodgdon's data online shows a starting charge weight of 35gn and a max of 37.5 so I'm a little confused as to why they are so much different.

I'm loading for the 105amax in Lapua brass seated at 2.800" OAL with CCIBR2 Primers.

Currently I'm preparing to load these five charge weights.
39gn
39.5gn
40gn
40.5gn
41gn

Quickload shows my max pressure if 54,000 at 41gn so I'm fairly comfortable knowing I'm not pushing the limits too much, but the data from the Hogdgon website with a max charge weight of 37.5gn has me second guessing myself. I assume it's because of a different seating depth that was used from the Hodgdon data.

Am I ok to go ahead with the 5 charge weights I listed above?


Thanks,

Ryan

 

[Rmitch223]

TTT

 

[nvbroncrider]

I've never had a problem with IMR powders if it drives tacks and your happy with it don't change it.

 

[Guy Miner]

Ryan - it's frustrating when printed reloading sources disagree.

I tend to be conservative when loading for a new cartridge but I can't imagine Hornady recommending an unsafe charge.

I'd recommend though - to be on the safe side - starting with the lowest recommended charge, which looks like it comes from Hodgdon...

This isn't the only one that is a fairly big discrepancy between two respected sources. If in doubt, start with the lowest recommended charge.

FWIW, Guy

 

[onesonek]

Charge differences are likely due to different test barrel be my guess. It isn't all that uncommon, however big as Guy mentioned. I go with Guy's thoughts/proceedure when it comes down to it. It's always good to cross reference data. Otherwise I go with the powder mfg., rather than the bullet mfg. data also

 

[DrMike]

Ryan - it's frustrating when printed reloading sources disagree.

I tend to be conservative when loading for a new cartridge but I can't imagine Hornady recommending an unsafe charge.

I'd recommend though - to be on the safe side - starting with the lowest recommended charge, which looks like it comes from Hodgdon...

This isn't the only one that is a fairly big discrepancy between two respected sources. If in doubt, start with the lowest recommended charge.

FWIW, Guy

Excellent advice, Ryan. Also, it is always a good idea to check the Hornady web site for Errata. There are almost always a number of errors in their handbooks (http://www.hornady.com/support/handbook-updates-errata).

 

[Rmitch223]

I was thinking about loading some lower charges at 37gn, 37.5, 38, 38.5, then 39, 39.5, 40, 40.5, 41.

Just to be safe, most of the people I have talked to say there load is around 41 - 42 grains, but when I saw that hodgdon's max I gotta a little nervous starting my workup at 39gn.

But then again, If I'm good to go with no pressure issues at a 39gn starting charge I would'nt be wasting time, powder and bullets at those lower charge levels that Hodgdon recommends

 

[Guy Miner]

As a compromise - you might just load one or two cartridges with the lower charge weights.

Mark the cases with the powder charge using a Sharpie. Shoot them over a chronograph, note the velocity, examine the cases. Likely you'll be fine with the heavier Hornady charges, but it might be interesting to shoot a few of the lower charges, just out of curiosity if nothing else.

Regards, Guy

 

[RiverRider]

I like Guy's idea. In fact, when I find myself totally in the dark and full of doubt I do exactly that. The way I figure it, you can't find an accurate load shooting two-shot groups, but you can sure weed out the poor loads when a two-shot group runs two inches.

 

[Rmitch223]

Results!

5 shot groups at 100yrds.

Hard to choose which charge weight is best, what do you guys think?

38gn and 39.5 seem to be really close.

Couldn't upload the target pics here for whatever reason.
Please visit the below link to view photos.

http://forum.snipershide.com/showthread.php?t=172778

Thank you,

Ryan

 

[usmc 89]

Once you get your accuracy down to where you want it i would let a chronograh decide which one is best. I believe you will find a good chronograph will be one of your most valuable assets when it comes to long range precision and load development. Buy the best you can afford.

 

[SJB358]

Results!

5 shot groups at 100yrds.

Hard to choose which charge weight is best, what do you guys think?

38gn and 39.5 seem to be really close.

Couldn't upload the target pics here for whatever reason.
Please visit the below link to view photos.

http://forum.snipershide.com/showthread.php?t=172778

Thank you,

Ryan

Ryan, what kinda speeds were you seeing. Seems pretty slow, unless you are just looking for an accurate target load, but I think you have some room to grow for sure.. Couldn't see your targets, but I imagine they are great.