The Traveling Breech Plug
#32
ronlaughlin
When you say 'crush fit' are you saying when you close the rifle you should feel the crush of the primer nose on the primer shelf in the BP.... or you should feel the primer walls crush fit against the walls of you primer pocket?
The W209 is the longest primer out there but it is one of the skinniest... The CCI is shorter than the W209 but it is bigger in diameter - fatter
So which 'crush fit' might you be suggesting. When we were designing the new Lehigh BP - we started with the thought of fitting the primer to the primer walls of the BP. That di not work well becase it limited you to one primer. We eventually ended up creating a primer shelf that the nose of the primer went up again to create the primer seal. When you put a W209 primer in a Lehigh BP you will actually crush the nose a few thousands again the the primer shelf in the primer pocket.
When you say 'crush fit' are you saying when you close the rifle you should feel the crush of the primer nose on the primer shelf in the BP.... or you should feel the primer walls crush fit against the walls of you primer pocket?
The W209 is the longest primer out there but it is one of the skinniest... The CCI is shorter than the W209 but it is bigger in diameter - fatter
So which 'crush fit' might you be suggesting. When we were designing the new Lehigh BP - we started with the thought of fitting the primer to the primer walls of the BP. That di not work well becase it limited you to one primer. We eventually ended up creating a primer shelf that the nose of the primer went up again to create the primer seal. When you put a W209 primer in a Lehigh BP you will actually crush the nose a few thousands again the the primer shelf in the primer pocket.
#33
Nontypical Buck
Thread Starter
Join Date: Aug 2008
Location: Rapid City, South Dakota
Posts: 3,732
The caliper tell's me what the 'crush' is. For example, the table you posted the other day had the STS primer being 0.294" long. When i close my Accura with it's current breech plug, i cannot really feel any 'crush'. However, when i open the breech, and then remove the unfired STS, it will measure 0.291". This is the 'crush' that makes for zero blow by, a shiny clean spent primer, and clean scope bottoms. Myself, i cannot feel this 'crush' when i put the Accura into battery, however, i can feel it when i put my Omega into battery.
What was happening to the CVA guy, is, he was 'smushing' the W209 primer. They were sticking, and leaking, because they were deformed by being 'smushed'. In that instance, they were forced tight to the side wall of the primer pocket, not just the shelf. Of course this is only conjecture on my part; i wasn't consulted nor was i there, but it is the only logical explanation i can come to. When i received the plug, and measured it, and examined the primer pocket, my inspection verified what i already was certain of; the primer pocket was not too deep.
#34
Not exactly. I am saying this is indeed how the 'crush' happens, but i don't necessarily feel it.
The caliper tell's me what the 'crush' is. For example, the table you posted the other day had the STS primer being 0.294" long. When i close my Accura with it's current breech plug, i cannot really feel any 'crush'. However, when i open the breech, and then remove the unfired STS, it will measure 0.291". This is the 'crush' that makes for zero blow by, a shiny clean spent primer, and clean scope bottoms. Myself, i cannot feel this 'crush' when i put the Accura into battery, however, i can feel it when i put my Omega into battery.
The caliper tell's me what the 'crush' is. For example, the table you posted the other day had the STS primer being 0.294" long. When i close my Accura with it's current breech plug, i cannot really feel any 'crush'. However, when i open the breech, and then remove the unfired STS, it will measure 0.291". This is the 'crush' that makes for zero blow by, a shiny clean spent primer, and clean scope bottoms. Myself, i cannot feel this 'crush' when i put the Accura into battery, however, i can feel it when i put my Omega into battery.
[/quote]What was happening to the CVA guy, is, he was 'smushing' the W209 primer. They were sticking, and leaking, because they were deformed by being 'smushed'. In that instance, they were forced tight to the side wall of the primer pocket, not just the shelf. [/quote]
I can picture that as we had the same problem when we set the shelf for a Fed 209a... when we then used a W209 we crushed it to the point of deforming it and squeezing it against the prime pocket wall + I think it dod leak.
Of course this is only conjecture on my part; i wasn't consulted nor was i there, but it is the only logical explanation i can come to. When i received the plug, and measured it, and examined the primer pocket, my inspection verified what i already was certain of; the primer pocket was not too deep.
mike
#35
Fork Horn
Join Date: Dec 2009
Posts: 195
I recieved one of Ron's plugs to try in my Kodiak, last week or so. A work of art IMO. I'm a pipefitter, so pretty threads don't do anything for me. The plug threaded as good or better than the OEM. The plug in the photos, threads, are not gonna hurt the threads in the ML. If so, I'd be more worried about the barrel material. I got my calipers out and found Ron's to be 0.011" longer, not a big deal. The Federal 209A primers I've been using fit perfect. + I can always use a STS or CCI. Plenty choices, again IMO. A Win 209 was too long, so there's no way the pocket is too deep. Too shallow for the W209, but not all the other choices recommended by Western(BH209). You wanna talk about blowback! the OE plug is terrible, crud on my scope, my face. Anything will be better.
Now I'm not an expert by any stretch, and when it comes to 209 stuff, I'm a borderline newbie, and appreciate all I am learning here, and commend Ron for trying to help us shoot better. But for $13.00 and a 3 day turnaround, best bang (pun intended) for the buck I've ever had, even if it doesn't work out. Will try it Sunday (going north Mi. ML season) and report. Thanks again Ron L.
Now I'm not an expert by any stretch, and when it comes to 209 stuff, I'm a borderline newbie, and appreciate all I am learning here, and commend Ron for trying to help us shoot better. But for $13.00 and a 3 day turnaround, best bang (pun intended) for the buck I've ever had, even if it doesn't work out. Will try it Sunday (going north Mi. ML season) and report. Thanks again Ron L.