H4350 load work up - 243 Win.

[Ryan M.]

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

 

[Ryan M.]

TTT

 

[CanusLatransSnpr]

I recommend going .3gr. increments and start at the minimum charge they give! You never know, you might find an accurate node in the lower end of the powder charge range? Once you get a good charge play with seating depth till you get it as good as can be!

Mike

 

[Ryan M.]

I recommend going .3gr. increments and start at the minimum charge they give! You never know, you might find an accurate node in the lower end of the powder charge range? Once you get a good charge play with seating depth till you get it as good as can be!

Mike

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.

 

[jde650]

I am not sure what loading manual you are looking at but Hodgdon on line loading data lists 43.5 grains H4350 as Max @ 58,800 PSI for the and 41.0 for starting load.


Jim

 

[jde650]

Sorry, I was thinking of the 6mm rem. My old eyes dont see to well or my brain doesnt function to well.



Jim

 

[Ryan M.]

Here is the Quickload data Ive been looking at.

37gn seems fairly conservative.

Second page is the Quickload data at 41gn that I plan on working up to, still seems pretty safe in regards to pressure...?

 

[243DH]

I run 42.0 gr under a 107 non moly smk in a 24" 1-8 6 grove criterion barrel, 3130fps. In a 25.5" 1-8 4 groove Krieger i use 42.5 gr under the same 107smk, gets me 3100. Win brass and br2, ob the 8 th loading on the brass. Also use h4831sc in 2 other243 1-8 barrels, they are 26&28" long tubes, brux and LW.

 

[Bamapse]

I am shooting 105 amax with 39.2gr of h4350 and they seem to be great. When I get home, I will see what my lengths are and get back to ya

 

[Ryan M.]

So far 38gn, 39.5 & 40.5 have been the sweet spots.

As soon as I narrow it down to one charge weight im going to start tweaking the seating depth .005 in each direction. Ive never changed the seating depth after working up. How can I be sure there will be no pressure issues when seating the bullet .005" more into the land and .005" away from the lands?
Anybody have a rule of thumb for this or is worrying about pressure after changing seating depths not important?

 

[boltgunluvr]

One's accuracy load is generally NOT a hot load. Most of mine are in the lower half of the charge range.

 

[Ryan M.]

Bump,

For advise on seating depth adjustments after finding a optimal charge weight.

 

[eric32]

check out this thread as well might provide you with some good information

http://forum.accurateshooter.com/index.php?topic=3808095.0