View Full Version : Firing Pin strike depth & 6 vs. 12

03-17-2011, 07:12 PM
We recently tested a couple of Turbo bolt conversion kits on 2 different rifles, and we sent the data to Larry "Landy" Landercasper to evaluate the numbers. Landy is exceptionally good with statistics and analysis. He created a blog to show all of the testing and his analysis.

All of the testing was done by myself and the owner of the two rifles at the Killough Shooting Sports 'Proving Grounds' which is a 20'x20' room on the end of an eight foot wide and eight foot tall hallway that is 50 meters long. It is completely enclosed and provides a great environment for testing. All of the testing was done at 50 yards.

When testing the 6 o'clock conversion kit vs. the standard Turbo bolt you have a few differences other than the obvious firing pin location. The conversion has a slightly larger diameter bolt body and gives a slightly different headspace. Unfortunately I failed to measure the diameter of the bolt body, but you can tell with the naked eye that it is a slightly different size. This might help or it might not, I am not sure. The firing pins are also shaped differently with the 6 o'clock pin leaving a much larger foot print. Again, this might help or it might not, I am not sure.

Everything can be seen here

03-17-2011, 08:03 PM
We appreciate your time Dan, Landy and others thank you.

I have been reading a lot on Bill C's web site the last couple of days and your report confirms exactly what i have concluded. Bill is a lot smarter than science ! Bill Calfee says the 6 o'clock pin is best for accuracy so sorry your experiment was flawed (concluded no difference in a 6 or 12 o'clock pin), but it was a valiant effort trying to prove Bill correct. Better luck next time.

Bill B
03-17-2011, 09:29 PM
Thanks guys. Read Landy's analysis of the data carefully. Those not used to looking at data often mis-interpret it. Landy got it right.

03-18-2011, 08:41 PM
What are you really trying to say????? Speak up! Thanks Landy!

03-20-2011, 06:56 AM
If the variations are not significant, the conclusion is that they are due to random chance. For the test there appears to be no significant difference in the firing pin position. This makes perfect sense and the data supports the conclusion. The shooters appear to have conducted a pretty good test and tried to control as many variable as possible Good job guys