Hornady vs. Hodgdon Load Information

[tplace]

I'm getting back into reloading after many years away from it. I have a new Hornady AP progresive press and (thanks to Hornady) a large supply of 185gr .45cal jacketed bullets. During my research of load data I referenced the latest Hornady manual and referenced the Hodgdon site which lists the 185gr Hornady bullet with Tightgroup (the powder I am using), there is quite a difference between the two sources.

Hodgdon lists 185 GR. HDY JSWC Hodgdon Titegroup 1.135" OAL

Starting Load 5.0gr @ 892fps

Max Load 5.5gr @ 956fps

The Hornady Manual goes 1.225" OAL

Starting Load 5.5gr @ 850fps

Max Load 6.1gr @ 950fps

Those are pretty big differences in powder weight. Am I missing something here? Does anyone have a pet load for the 185 using tightgroup?

Thanks for the clarification.

[The_Vigilante]

The OAL for the Hornady looks very short-like for a 9mm load. You may want to recheck it.

[acekc]

The 1.225" OAL in the Hornady manual is for the XTP; Hornady lists an OAL of 1.135" for the SWC which matches Hodgdon's OAL for the same bullet.

Powder weight differences between different manuals are pretty common - I usually consult multiple sources to get a feel for the overall weight range and then start low and work up with a chrono while looking for pressure signs. More than likely the differences are due to Hornady and Hodgdon using different guns for their testing.

Hornady used a Colt Government Model which has a barrel length of around 5". AFAIK Hodgdon doesn't provide any information on the gun they use for testing a particular caliber, but if they used a gun with a longer barrel it would explain why they got similar velocities with 0.6gr less powder.

[FLSlim]

Welcome. The differences in bullet design and OAL alone could easily account for the difference you report. When you are reviewing loads from manuals be sure you are comparing apples to apples!

[Graham Smith]

Differences in bullet length and OAL can change the pressure which can change the velocity.

[Doc Hunter]

What was the tested barrel lengths for each?

[tplace]

Thanks for the replies, I've been wrapped around the axle at work or I would have responded earlier.

Aceke: you are right two different bullets, I don't know what I thought I read. I did a push test with the barrel of my Para 1445 with both the 185 XTP and the 200 XTP, when I measure the OAL of the round they both are right at 1.207. I'm thinking 1.210 for the loaded round would be a good number.

Any thoughts?

Thanks!