Comparing loading data for the Swedish Mauser
Posted: Fri Apr 12, 2013 4:29 pm
Last year I started loading for a 6.5 x 55 Swedish Mauser - As I intended to use VihtaVuori powder, it seemed logical to use their loading data... Unfortunately I had problems with the loads, varying from sooting to signs of pressure (note: the 'signs' may also have indicated 'poor fit' or generous chamber, and not necessarily pressure).
Having spoken to BLU about it, he very kindly sent me all the loading data he had for the Mauser; which I've now compared...
I already had the Vhit and Lyman manuals, and Blu sent me data for Speer, Barnes, Sierra, Nosler and Hornady - The first obvious comparison is that most represent a specific bullet manufacturer, where as the Vhit represents a powder, and the Lyman is the only independent one.
All the manuals, apart from the VihtaVuori one, give an introduction to the round; and warn about the differences in loading for a modern Mauser and a milsurp - The Hornady manual is the only one to mention the 29" barrel on the M96, and actually used one for the testing...the others just quote a test barrel lenth; which is away several inches shorter.
The data I was specifically looking for was for Viht N160 and a 140 gn HPBT bullet...
The VihtaVuori manual gives: COL of 3.110 for the exact bullet I am using - Starting load of 43.4 - Max load of 46.7
The Speer and Barns manuals couldn't be used for comparison as they neither quote Viht powder or a comparable bullet for this load.
The Sierra manual give a COL of 3.050 for the exact bullet I am using...but doesn't quote Viht powder.
The Nosler and Hornady manuals both give more or less the same data - The 140 gn bullets quoted are not exactly the same as an SMK, but are clearly fully seated at a COL of 3.025 - And starting loads of 37.0 - Max of 41.0
The Lyman manual gives a COL of 3.050 for a HPBT - Starting load of 39.5 - Max load 44.0
So in comparison: The VihtaVuori manual gives a COL that leaves very little of the bullet in the case neck, where as all the other manuals suggest seating either more than half way down the neck, or fully seated - And the Viht starting load is between 4 and 6 gn higher than all the other manuals.
My problems developing a load for this round were partly down to my lack of experience (some may say stupidity) in not fully understanding the differences in pressure caused by what seem to be small changes in seating depth - However I do think that for this specific caliber the Viht manual may not be the best for a relative beginner loading for an old milsurp...
Having spoken to BLU about it, he very kindly sent me all the loading data he had for the Mauser; which I've now compared...
I already had the Vhit and Lyman manuals, and Blu sent me data for Speer, Barnes, Sierra, Nosler and Hornady - The first obvious comparison is that most represent a specific bullet manufacturer, where as the Vhit represents a powder, and the Lyman is the only independent one.
All the manuals, apart from the VihtaVuori one, give an introduction to the round; and warn about the differences in loading for a modern Mauser and a milsurp - The Hornady manual is the only one to mention the 29" barrel on the M96, and actually used one for the testing...the others just quote a test barrel lenth; which is away several inches shorter.
The data I was specifically looking for was for Viht N160 and a 140 gn HPBT bullet...
The VihtaVuori manual gives: COL of 3.110 for the exact bullet I am using - Starting load of 43.4 - Max load of 46.7
The Speer and Barns manuals couldn't be used for comparison as they neither quote Viht powder or a comparable bullet for this load.
The Sierra manual give a COL of 3.050 for the exact bullet I am using...but doesn't quote Viht powder.
The Nosler and Hornady manuals both give more or less the same data - The 140 gn bullets quoted are not exactly the same as an SMK, but are clearly fully seated at a COL of 3.025 - And starting loads of 37.0 - Max of 41.0
The Lyman manual gives a COL of 3.050 for a HPBT - Starting load of 39.5 - Max load 44.0
So in comparison: The VihtaVuori manual gives a COL that leaves very little of the bullet in the case neck, where as all the other manuals suggest seating either more than half way down the neck, or fully seated - And the Viht starting load is between 4 and 6 gn higher than all the other manuals.
My problems developing a load for this round were partly down to my lack of experience (some may say stupidity) in not fully understanding the differences in pressure caused by what seem to be small changes in seating depth - However I do think that for this specific caliber the Viht manual may not be the best for a relative beginner loading for an old milsurp...