270win 120grsst
- Thread starter Guru 270
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CAUTION: The following post (or a page linked to) includes or discusses loading data not covered by currently published sources of tested data for this cartridge (QuickLOAD or Gordon's Reloading Tool data is not professionally tested). USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assumes any liability for any damage or injury resulting from the use of this information.
Welcome to the forum.
My Hornady book (#10—I haven't purchased #11 yet) doesn't list the 120-grain SST, but it's got the 130 and a couple of 110-grain bullets, and squinting between the lines (right between a 2600 fps load for a 130 and a 2800 fps load for a 110), it looks like 41.8 grains of IMR4064 would be about where you want to go. I put the warning in the post because this isn't published data that I have my hands on, but these are both starting loads for their respective bullets that I am interpolating, so there should be no pressure issue. Use a chronograph to check what velocity you actually get. Note that the 4064 is very low on case fill with this load, so having the powder back over the primer will give higher velocities.
That said, the pressure is low with that little powder, so a faster one like IMR 4198 is likely to burn cleaner. Around 39 grains for a start with that.
Also, note that if you call Hornady and ask for load data, they will probably just give it to you.
Welcome to the forum.
My Hornady book (#10—I haven't purchased #11 yet) doesn't list the 120-grain SST, but it's got the 130 and a couple of 110-grain bullets, and squinting between the lines (right between a 2600 fps load for a 130 and a 2800 fps load for a 110), it looks like 41.8 grains of IMR4064 would be about where you want to go. I put the warning in the post because this isn't published data that I have my hands on, but these are both starting loads for their respective bullets that I am interpolating, so there should be no pressure issue. Use a chronograph to check what velocity you actually get. Note that the 4064 is very low on case fill with this load, so having the powder back over the primer will give higher velocities.
That said, the pressure is low with that little powder, so a faster one like IMR 4198 is likely to burn cleaner. Around 39 grains for a start with that.
Also, note that if you call Hornady and ask for load data, they will probably just give it to you.
Based on Hornady's data, H4350 would run about 48.6 grains. The heavier charge will add to recoil and the slower burn rate powder will reach velocity at a lower peak pressure that won't burn it as cleanly and consistently as a lighter charge of a faster powder that reached the same velocity.
VV N135 looks promising to me as a good burn rate compromise with better bulk for the big case, but it's not available everywhere.
VV N135 looks promising to me as a good burn rate compromise with better bulk for the big case, but it's not available everywhere.
stagpanther
New member
Rather unusual pursuit--a soft-shooting 270 win. Following with interest.
Keep in mind the 120-grain Barnes bullet in the Hodgdon data is for the obsolete FXB type, which was a smooth surface copper solid. They achieved higher start pressures with less powder than an SST would do. H414 and 760 are both canister-grade WC760, one of the military powders made in the St. Marks, Florida plant. They are slower than H380, which is slower than IMR 4064. I think, because of potential ignition issues, IMR 4064 or faster is going to play more nicely in this reduced velocity exercise with the SST.