need a starting load for 300gr XTP in a 7.5" blackhawk.

[RWE]

I'm firing up an inherited 1st year production Blackhawk in 45 colt for whitetail.

I had made some wheelweight cast 280gr SAA's, but I've delegated those to the SxS 45 colt rifle I built, due to supply, and the only thing I have to shoot on hand for the hand cannon are some 300gr XTP's. Even if I had some more WW, not sure I would have time to cast, as I'm also trying to get a Pedersoli Kodiak 54 running.

Anyone have a good load they've been using so I have a place to start to minimize lead time?

Thanks.

[44MAG#1]

I wouldn't call a 45 Colt a hand cannon but Hornady's book lists starting loads for the bullet. If you don't have loading books I would suggest you get more than one.
Speer #14 and Hornady's would be the two I would get first.

[RWE]

I have Lee and Lyman's already.

Unfortunately, with the powder shortage running rampant here, I would be limited to H110, bullseye and unique as my only available pistol powders.

My Lyman book doesn't list the 300 XTP, and Lee does, but does not list my available powder.

[44MAG#1]

Hornady book 4th Edition 21.3 gr W296/H110 at 1.585 OAL Win cases and Win primers. This a MAXIMUM load reduce what you want but I would not go below 10 percent even though Hornady lists 17.3 as their start.
Do as you wish.

[Sensai]

For hunting, I'd recommend the 110. Go to the Hodgdon.com site and look in their load data for a good load. H110 doesn't like to be babied, and the BE and Unique don't like to be stoked too much.

[Zymurgy50]

Speer #13 shows a 300gn JHP over 21.1gn H110 @974fps for a starting load, 23.5gn H110 @1156fps for max load. Both loads using magnum primers. COL@ 1.640"
FOR RUGER AND CONTENDER ONLY!!!!!!!!!!!!!!!!!!!

[44MAG#1]

Hodgdons used the 300 Speer as does Speer themselves and it doesn't seat as deep in the case as the Hornady. If you use Hodgdon and or Speer data seat the Hornady out. Then one MAY be able to work up slightly with the Hornady seated out.
This is why asking for data on the 'net is a somewhat risky business.

[Jupiter7]

Hornady #8 only lists Ruger only loads for the 300gr xtp.

They don't list h110, but do list w296(same powder).

Xtp 300gr-model #452230
the 2 cannelure version-not XTP MAG
COL 1.580
Start 17.9gr w296 1050fps
Max 21.7gr w296 1300fps

For xtp mag model#452235 same load data, COL 1.655"

[RWE]

Thanks Gentlemen.

I'll roll some this weekend and see how it does.