
02202023, 09:11 AM  #13  

Quote:


The Following 3 Users Say Thank You to Mike Franzen For Your Post: 
02202023, 11:38 AM  #14  

By using direct proportions to convert 12g (using a .729 bore) to 8g bore/chokes, it works out to
IC .010 = .012, M .020 = .023, IM .030 = .035 and F .040 = .046. My bores are R .846 and L .847. R choke is .828 (.018) or LM. L choke is .831 (.016) which should also be LM. I know someone will double check this and definitely tell me if I'm wrong. Using the 3.14 x radius squared I still come up with LMM choking. 

The Following User Says Thank You to Mike Koneski For Your Post: 
02202023, 01:35 PM  #15  

Naaah Mikey, that's an oversimplification. You must use the surface area of the 12 gauge and 8 gauge bores, as measured. On the measurement it's my experience that bore mikes made to measure up to 12gauge bore diameters will "drift" and read somewhat oversize with 10gauge bores, and no doubt an even greater drift if the mike can be expanded for 8gauge bores. From what I understand the nominal 8gauge bore is .835" diameter. Probably best to "slug" the barrel with a somewhat larger lead slug and measure same with a caliper or regular 1" outside mike.


02202023, 02:08 PM  #16  

Using the Pi x R squared for bore and choke of 12 and 8 should give me the surface area. Still came up with LMM.


02202023, 02:14 PM  #17  

As for slugging the bores and micing the slugs, I won't be doing that. I don't need to know an exact choke constriction. Choke is irrelevant. Just put the muzzle at the right place and you break the clay or kill the bird. You know the thought process behind it my friend.
I was just curious as to how the chokes break down compared to the 12g as the OP was asking about. Tight chokes leave diesel smoke. Open chokes leave big pieces. I say "Smoke 'em if you got 'em!!" 

The Following 2 Users Say Thank You to Mike Koneski For Your Post: 
02202023, 03:13 PM  #18  

Mike et al., I had some time and plugged .835" bore into my choke calculation excel spreadsheet and here are the theoretical constrictions for 8gauge. As always actual choke efficiency (percentage in 30" dia circle at 40 yards) depends on other factors to include shot sizing, bore "roughness measurement", choke profile and others. Bottom line, there's no substitute for testing on paper.
8Gauge IC = 13 thou Mod = 24 thou IMod = 34 thou Full = 47 thou XFull = 52 thou 

The Following 2 Users Say Thank You to Frank Srebro For Your Post: 
02202023, 04:20 PM  #19  

Good to see our numbers are only off by .001". Probably due to me using .846 instead of .835. THX!!


The Following User Says Thank You to Mike Koneski For Your Post: 
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