Shopdog
posted this
22 August 2018
Joe,very slight tangent.....
"Although" most handloaders suggest not using a roll crimp on bolt action rifle cartridges..... I've found them almost indispensable.
Most of my shooting is done with hunting in mind.As such,the rounds have to survive a rather,brisk trip up through the magazine.I also like a "jam" fit.
A slight rolling in of the case mouth acts as an abutment to the bullet seating depth.Consider this to be the final bit if seating.
So,we have an EXTREMELY well fitted,swaged bullet with a roll crimp. It,and the case,ain't goin no where at the point of ignition.
This isn't "tension" in my book.Tension is better described as an interference "fit".Very easily changed..... also this isn't based on seating friction.Which is independent of tension because there's a huge difference in how the interior of the neck and the lubed bullet interfaces during the seating process..... not to mention annealing and/or brass hardness.
In my example,crimp & jam.... this is where "hold" enters the picture.Also can be corrosion.... bullet can "weld" itself to case neck.... as in shooting old ammo.To say tension has no bearing on acc is very myoptic... it may not.How's that working for you? To say,never roll crimp is the same thing.Good luck with your project.