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Jim
11-15-2008, 10:53 AM
The only section here about shotguns is for casting for them, so I figured I'd post here 'cause near 'bout everybody drops in here to look.

I went to an old fashioned turkey shoot last night and smoked everybody!:Fire: Using a borrowed Winchester mod. 1400 with a .690 "Super Full" choke, I shot 7 times and won 6 turkeys. My buddy that went with me gave up on his old pump and started using mine. He registered on the ham shoots, shot 4 times and won 3 hams! I got to thinking about all this and I'd like to get some input from the shotgun hunters here.

I understand that the size of a choke certainly affects the pattern of the shot. Would the LENGTH of the barrel have an effect on the pattern as well given that the choke is the same?:confused: If I were to have a barrel cut and tapped for screw-in chokes, how short could I have it cut and the choke still perform to it's design?

I've never been comfortable with unusually long barrels. That being said, I'd like to know if I can get the same effect with a relatively short barrel so I'd be comfortable handling and shooting the shotgun.

The line forms on the right.:-D
Jim

missionary5155
11-15-2008, 12:04 PM
Greetings I have a Fox B 30 inch barrels. I had a S&W pump (996 ?) police pump model with a 24 inch cylinder. I reamed and threaded both for thin wall screw in chokes. All this was purchased from Brownell´s. My Fox B with the Full choke Choke attached would hold a much better pattern than the S&W using the SAME full choke (switching between barrels) and the same load. We also experimented with the Modified Choke between the two barrels same load and the 30 inch barrel (either side) always shot a better group. My son still has the S&W... is taking it deer hunting today in Minnesota.
I also ran the same experiment with my Fox B using 26 inch barrels I also threaded for Thin Wall chokes. Again using THE SAME Choke between the 30 inch and the 26 inch mounted on the same frame the 30 inch always gave a tighter pattern with various shot sizes. I do not have that book with me here in Peru but it was enough difference that I would NOT cut off a barrel thinking it would continue to shoot the same...

870TC
11-15-2008, 12:41 PM
I don't want to get into a flame war here. Just a couple of things about shotgun barrels you may want to investigate further... Barrel length is less important then the dimensions of the inside of the barrel AND the choke. Pattern will be affected by the forcing cone (just forward of the chamber) the inside diameter of the bore (in thousands of an inch), the amount of constriction in the choke (compared to the bore diameter), and on some guns there is second taper or "forcing cone" that leads up to the choke.
Missionary5155's experience with using the same screw in full choke in two different barrels is a prime example. The "choke" was the same but were the inside dimensions of the bores the same?- most likely they were not. So even though he used the same choke, he got different sized patterns. Why?, because "choke" is the amount of constriction or difference in thousands of an inch, between the bore diameter and the choke diameter.
If you put the same screw in choke in two different guns, one with a large bore and one with a tighter bore, you will get different patterns because the amount of change between the bore and the choke is different in each gun.

wire nut
11-15-2008, 12:50 PM
I agree with 870TC. We used to go to turkey shoots all the time and we woulg shoot our targets at 47 yds. We shot at a target with a 3 inch bullseye and a 6 inch circle as the outher ring. Some of our guns would blister a target at 47 yds but move the target back to 50 yds and that was a different story. You wouldn't think 3 yds made that much difference but it did.We shot mostly a remington model 29 at 47 yds and a model 12 winchester at 50 yds. I would about bet that half of the 29"s made were within a 100 mile radius of where i live at one time.

Firebird
11-15-2008, 07:34 PM
One of the many things that can open up a pattern is the powder gas blowing through the pellets just after the pellets exit the muzzle. A longer barrel means that the powder gas has expanded into a larger volume, therefore will have a lower pressure at the muzzle. So the pellets shouldn't be disturbed as much, and the pattern should be a little tighter and a little more even in a longer barreled gun than a shorter barreled gun. This is offset to a large extent by the plastic wad cups, which protect the pellets from the powder gases as everything is coming out of the muzzle. This is what makes ballistics so much fun, so many variables that work with and against each other until you go dizzy :veryconfu trying to keep up with them; and find numerous examples of guns that support and contradict whenever you actually test them.

missionary5155
11-15-2008, 08:04 PM
Greetings 870TC I would agree with you about the constriction ratio between barrels. That was one of the reasons I decided to try the two different lenghth Fox B barrels. But again there could be a difference even in two barrels from the same factory for the same model...
As of yet I have not brought myself to sacrifice a set of doubles to find out for sure.
Maybe some day I will get a single shot and start chopping. I wonder how many a person wpould have to try before there was enough evidence to make an honest evaluation ? Sadly the tooling to get into just ONE type of choke tube is costly... but the reamer is a reamer and can ream for any type.. Like Firebird stated.. the variables can make ya go dizzy....

fecmech
11-15-2008, 11:13 PM
Missionary--There could be a difference between the barrels on the same gun! Barrel tolerances are pretty loose on shotguns. I had two Browning barrels made by Miroku in Japan after Browning went there for their manufacturing. These were 20 ga. bbls and there was .005 difference between the 2, essentially a 1 choke increase between the two barrels using the same choke tube.
I personally don't think barrel length has much to do with pattern. The trick to getting tight patterns is to get the shot out of the barrel still round. That requires #1. hard round shot to start with, #2 a cushioned launch of the shot charge with minimal damage and #3 smooth gentle barrel transitions through the forcing cone and the choke.

870TC
11-15-2008, 11:36 PM
missionary5155, you may want to check out Bob Brister's book "Shotgunning: The art and the science" He did a lot of similar testing. Hope your boy found something to shoot at, deer seem to be scarce in Mn this year.

dakotashooter2
11-16-2008, 01:41 AM
Also while one would think a choke is a choke is a choke, that may not be true. Various manufacturers may vary in what they consider a "full" choke. Ones full may be the next's modified or improved modified. I think this happens mostly when they designate a choke for lead, or non toxics which generally shoot a tighter pattern with a more open choke. Extended chokes toss in another variable. I purchased my first set of carlson extended chokes this year and was really impressed at the pattern improvement. I have been struggling killing ducks dead since steel was made mandantory. This year I only had 2 that were not dead when they hit the ground. In an odd twist, I have four tenner inserts for my 20 ga. and when fired through an x full extended turkey choke the lowley 1/2 oz410 load patterns better than a 1 oz 20 ga field load out of the same gun and choke. It just seems to be a lot of trial and error to see what your gun likes.

Jim
11-16-2008, 04:28 PM
I started advertising around through my network that I'm in the market for a turkey gun. I found one. A good friend of mine, of 13 years, has a Benelli Super Nova with a 26" barrel that he said he'd swap me "even steven" for a Remington 700 ADL in '06. I've got a 3.5X10X50 Cat's Eye scope that I'm gonna put on it for him.
He bought this gun NIB last year to hunt turkeys with and hasn't fire a full box through it. I've had the 700 for 5 years and haven't fire it in four. Sounds like a plan to me.