Doug at Hornady was nice enough to fax me some load data for my 300 H&H, I've never used Hornady bullets and don't have a manual. I'm hopeing work up some rounds in the morning and maybe make it to the range Sunday. But after looking their data over I've got a question for those of you who use Hornady bullets and their manual. Why is Hornady data so conservative???

Hornady list a 165gr @ 2900fps with 64gr of IMR 4350 max load.

Nosler list a 165gr @ 3118fps with 67gr of IMR 4350 max load.

Speer list a 165gr @ 3185fps with 69gr of IMR 4350
max load.

Barnes list a 165gr @ 3159fps with 69gr of IMR 4350 max load.

Sierra list a 165gr @ 3100fps with 69.1gr of IMR 4350 max load.

So what gives? Now I'm usually one to error on the side of caution and I rarely load max loads, I normally stay 1 gr below max. But the Hornady data seems weak to me. I mean we're talking 3 to 5 grains of powder less and 200fps + here. This just doesn't seem right. I know you start low and work up looking for signs of pressure. But based on this I'm tempted to start at 63 or 64gr with the Hornady and work up. Whats your experience with Hornady bullets and data?

[ 06-22-2002, 03:47: Message edited by: mark65x55 ]

And I say, IMR-4350 From 54.2 grains to 70.8 grains with Winchester WLR primer...but that doesn't mean anything.

You are going to get variations in loading data based on the equipment used to test the data, the firearm used to test the data, and the observations of the person doing the testing.

Reloading manuals are not the bible, they are general reference cookbooks. You can rest assured that oyu will not have problems with the minimum loads stated in any of the manuals, but the maximum load is totally dependant upon you and your firearm.

"...star low, work-up slow..."

I know different barrels, different primers.....and I under stand what your saying
but we're talking 3 to 5 grains of power here. I mean Speers starting load is 65gr of IMR 4350 and Hornadys max is 64gr of IMR 4350. Something about this just don't add up.

I went by the local gun shop this afternoon, the gun smith wasn't in, but as luck would have it he had a new Hornady manual on the counter. The fax Doug sent me is out of it. It list the 150gr sst in it. Anyway 3000fps is the max velocity listed for a 300H&H and a 165gr bullet.

Did you also consider that while all load you noted where for 165gr bullets, all the bullets are of different brands? Each may have different length of bearing surface, hardness of the jacket, bullet length, seating depth, etc. These factors can also effect the pressure of the load. Generally, given the same OAL, the longer bullet will be seated deeper into the case, effectively reducing the case volume.

I use Quick Load to model the effects seating depth changes with the same bullet and using different bullets of the same weight. On a 7mm STW, seating the bullet out .050, Quick Load predicts a drop in pressure of about 1000 psi. Also keeping the OAL the same, changing from a 160 gr Nosler Partition to a 160gr Speer Grand Slam, the program also predicts a 1000 psi pressure change.

Thanks for the replys.
I have, in part, found the answer to my question. It looks as if its the IMR powder that Hornady has a problem with. I was looking through my manuals again this morning and saw that Horady list Reloader 22 for the 165gr 300H&H. I also use, have some on hand and like Reloader 22. So I started compairing the numbers.

These are lister MAX. LOADS for the 300H&H with a 165gr. bullet using Reloader 22. These are MAX. LOADS USE CAUTION.

Hornady 71.8gr @ 3000fps

Nosler 72.5gr @ 3133fps

Barnes 72.5gr @ 3084fps

Speer Reloader 22 not listed

Sierra Reloader 22 not listed

So then I look at IMR 4831. Again these are lister MAX. LOADS for the 300H&H with a 165gr. bullet, USE CAUTION.

Hornady 65.8@ 2900fps

Nosler 70.0gr @ 3118fps

Barnes 70.00gr @ 31704fps

Speer 71.00gr @ 3185fps

Sierra 70.02 @ 3000fps

I then checked one more powder, Reloader 19. Again these are lister MAX. LOADS for the 300H&H with a 165gr. bullet, USE CAUTION.

Hornady 72.5@ 3000fps

Nosler 71.0gr @ 3099fps

Barnes 71.0gr @ 3181fps

Speer 67.0gr @ 3048fps

Sierra Reloader 19 not listed

So based on these numbers I'd say Hornadys data is on par with the others using Reloader powder, but when using IMR powder Hornadys data is conservative. Why I'm not sure. I wanted to use IMR 4350 powder and the 165gr SST bullet but I'm not going to give up 200+fps. Looks like with Reloader 22 I want have too. I'll start low, work up to about 1gr below max and hopfuly be happy. So now I've got some rounds to load. Thanks for your help.

Maximum loads are specific to a particular combination. And maximum loads are not a good idea to use for safety reasons.

I think that 70.8 grains of imr 4350 with any 165 gr bullet in a .300 H&H would be very hot. Also it was mentioned that the particular bullets bearing surface and with the Hornady's they have that shoulder on the bullet that changes the distance to the lands which may result in higher pressures.

I am shooting the 165 Sierra SBT and the 168 gr. Matchkings right now. Yesterday it was hot (85F) and a load with Remington .375 H&H cases and 71 grains of surplus 4831 and 215 primers had a little bolt lift effort. That's max. to me!

The velocity is about 3000 fps. I have not chrongraphed it since I started shooting it in cooler weather as I don't care what the max velociy is. A estimate of 3000 fps is close enough for me.

Feel inside those cases with a wire with a bent hook on it. That cartridge is good for only 5 reloads! I am up to 10 now with the stronger Rem cases but they have had it at 10 reloads.