Barnes TSX 300gr Flatpoint (45843) in 45-70 contender

[gr8ful]

Does anyone have any experience loading these bullets in a 45-70?  I was thinking of using load data for 300gr jhp from Lyman #49 with 27.0gr of IMR4227 (min starting load) but am concerned about seating depth, these bullets are long.  Should I seat to the last groove/cannelure for OAL 2.55"? This is a low density load so i have plenty of case capacity without compressing the powder.

[Silvertp]

I believe your latitude for seating depth ranges from longest oal of  "touching the lands" to the shortest oal of the furthest cannlure.  Seeing as how you are reloading for a single shot you don't have to worry about magazine length. 

The easiest would be to use one of the cannlure's and see how the loaded rounds perform for you.

Reasons to change the depth the bullet is seated would be to try and improve upon accuracy of the round or to increase powder space.

Silvertp

[Smokin Joe]

Use the Barnes data:

http://www.barnesbullets.com/images/45-70Marlin1895Web.pdf?PHPSESSID=42993a310ac29ecda4a917b2a5f5aaf8

[gr8ful]

Trouble is Barnes doesn't have a load for 4227, and I have a lot of 4227, I didn't want to buy a new can of powder just to try out these bullets.

[shot1]

You can use the start load that Lyman gives for the 300 gr Jacket bullets and be just fine. As has been suggested, find the OAL that is the most accurate.

[Smokin Joe]

Trouble is Barnes doesn't have a load for 4227, and I have a lot of 4227, I didn't want to buy a new can of powder just to try out these bullets.

The Barnes manual lists the following (for 1895 Marlin):

IMR 4227
38.5 gns @ 2002
41.5 gns @ 2159

OAL is 2.515
Case: Starline
Primer: Federal GM210M

[gr8ful]

Thanks Smoking Joe,  I don't have a barnes manual only the data Barnes lists on thier website, it looks like between the lyman manual and the Barnes manual I will have a lot of leeway in working up a suitable load, I think i will still start with 27gr and work up until I find something that suits me.  Thanks for the input everybody!

[gr8ful]

Just an update, I could not get a suitable load with 4227, started with 27gr and rem 9 1/2 primers, had a lot of unburned powder residue in the case and barrel, no pressure signs and recoil was mild.  Tried changing to winchester magnum primers, but still see a lot of unburned powder.  I am putting a heavy roll crimp into the last grove on the bullet.  Tried increasing the powder charge to 29 grains, but still seeing unburned powder.  So I went and bought a can of IMR 4198, 35gn with the magnum primers printed nice tight 25 yard groups.   Now i need to save up some newspapers to test out these bullets.

[buck460XVR]

Just an update, I could not get a suitable load with 4227, started with 27gr and rem 9 1/2 primers, had a lot of unburned powder residue in the case and barrel, no pressure signs and recoil was mild.  Tried changing to winchester magnum primers, but still see a lot of unburned powder.  I am putting a heavy roll crimp into the last grove on the bullet.  Tried increasing the powder charge to 29 grains, but still seeing unburned powder.

My experience with IMR4227 has been, if you're getting a lot of unburnt powder, your loads are too light. Up the charge and it usually cleans up. Your comment of mild recoil points in this direction.  IMR 4227 for me, works best at the upper end of velocities in straight wall cartridges. If you are looking for a powder puff load, IMHO, there are better powders out there.