Benchmark powder and Hodgdon Help!

[dgc940]

I bought a can of Hodgdon benchmark and loaded some 22-250's and man it was great good groups and metered great it looks like varget cut in half. well it's a fast burn rate and worked well with 50grn bullets so I thought I would try it in my 243win with nosler 55grn BT's but I could not find any data so I bought Hodgdons annual manual for 2007 and it said start at 39grains so I did and the first round sounded like a 300 wsm going off and I had trouble lifting the bolt flat primer and shinny skid mark on 30% of the rim all the signs of a hot load. Well I called Hodgdon and the guy said it's the right data and could care less. I then looked back in the manual and for a 58grn hornady bt it shows start with 35grains?????? can I just start over and start at 35grains with the 55's Now keep in mind my gun has never minded warm loads at all. I think the guy at hodgdon should have been a little more concerned dont you?

 

[mikecr]

I suspect that he didn't care cuz somewhere in the very beginning of the reloading manual, it probably says to start low and work up with each powder/rifle.

I would back off and get a feel for that powder lot, with your barrel, neck tension, etc. Do it everytime you change anything that has potential to increase pressure.

 

[bglenn]

dgc940
I looked in the 2006 annual manual and they list 39.0 gr. benchmark for a starting load with a nosler 55 gr. bt in it also. The manual also shows 38.5 gr. benchmark for a starting load with 60 gr. sierra hp bullets. I would say that the manual is correct. With my 2006 being out a year, I think if anything was wrong they would have heard about it by now. Your powder is burning right because it works in your 22-250. What type of scale are you using? Anyone can have human errors. Don't take offense but is this a possibility? It makes you scratch your head when everything look right. sorry I don't have a better suggestion.
Glenn

 

[dgc940]

Im using a RCBS 505 and it checks out with check weights.
I did start low at the bottom I also called Nosler and the Man there said it sounded wrong in his opinion like a misprint.

 

[rstreich]

Hodgdon's online data shows a max load of 41.5 gr. of Benchmark. They don't show a starting load. 39 gr. is about where I would have started given that info.

 

[ReedG]

I only loaded for .243 for a short time and do not have any personal load data. I also went to the Hodgdon site and to my 2004 and 2006 annual manuals and the 39.0-gr. load looks as though it should be no problem with a 55-gr. bullet. They list a load of 39.3 with a 70-gr. Sierra.

Above all, you have to go by what your rifle is telling you. Like the guys have said, back off to at least 37.0 and work back up until you see pressure signs. It is possible that you have a smaller chamber or tighter throat, thicker necks, etc.

 

[dgc940]

DGC940 When you wrote "metered great" what kind of powder measure are you using. On my DILLON 550 it sometimes will vary as much as two grains of powder . So "I WEIGH EVERY CHARGE ON THE SCALES" RANDY

It meters a lot like a ball powder with no cutting and meters very consistent but I also weigh every charge.

 

[Will]

dgc940, what OAL are you working with ? Do you have the bullet jammed into the lands ? IF so then that could be a problem. Anytime you have a load that has no jump there is going to be a major pressure increase. Doesn't matter caliber or bullet. So .. youmay want to seat some just a tad shorter in case and see if that helps.

 

[Dave]

Here in Oz where Benchmark is made, I checked the ADI site and they list 41.5 for the 55gr and 41.2 for the 60 grainer in the .243W.

I have found Benchmark to vary its burning rate considerably depending on the cartridge. It's much like Varget in the 6mm Br, but quicker than 3031 in a .308. It barely burns in a .222!

Dave