chiltech500
Member
Is OAL Really the Right Measure for Powder Loads
I am trying to reason out effects of bullet interior depth, i.e. more inside length = higher pressure round?
The reason this comes to mind is that I compared my Lymans’ last evening for 125 gr lead round with Titegroup and was surprised to see 3.2 gr as the max load vs a chart I’ve used that lists various powders at different bullet types/weights which shows Titegroup 4.0 gr for a 125 gr LCN. (Also, most forum posts speak about 4 gr of Titegroup with 9mm rounds).
The difference between the bullets was OAL as far as I could see, the lower powder charge OAL was 1.15 vs the higher load OAL of 1.125. I do not recall whose bullets they were using for each.
Correct me if I am wrong. When comparing one OAL vs another for pressure and load, the bullet used for measurement needs to be the same. There is no point in comparing say a 125 gr Lee LSWC vs a 125 gr Lyman of the same type (unless the bullet length below the mouth of the cartridge is the same)?
I compared a 125gr LSWC from Mo bullets vs a 125 gr LTC from Alpha Bravo. I measured the distance from the top of the lube strip to the bottom of the bullet. (I maximize OAL for accuracy) and the MO Bullet was .050 longer. To me comparing a load with these different bullets is useless without a chrono. Am I right about that?
I am trying to reason out effects of bullet interior depth, i.e. more inside length = higher pressure round?
The reason this comes to mind is that I compared my Lymans’ last evening for 125 gr lead round with Titegroup and was surprised to see 3.2 gr as the max load vs a chart I’ve used that lists various powders at different bullet types/weights which shows Titegroup 4.0 gr for a 125 gr LCN. (Also, most forum posts speak about 4 gr of Titegroup with 9mm rounds).
The difference between the bullets was OAL as far as I could see, the lower powder charge OAL was 1.15 vs the higher load OAL of 1.125. I do not recall whose bullets they were using for each.
Correct me if I am wrong. When comparing one OAL vs another for pressure and load, the bullet used for measurement needs to be the same. There is no point in comparing say a 125 gr Lee LSWC vs a 125 gr Lyman of the same type (unless the bullet length below the mouth of the cartridge is the same)?
I compared a 125gr LSWC from Mo bullets vs a 125 gr LTC from Alpha Bravo. I measured the distance from the top of the lube strip to the bottom of the bullet. (I maximize OAL for accuracy) and the MO Bullet was .050 longer. To me comparing a load with these different bullets is useless without a chrono. Am I right about that?
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