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How large should a pattern appear at 25 yards using a full choke?

I've read that this should give me results of about 3" but yesterday I patterned my Mossberg 190 and experienced 12" or larger.

Thanks.

Here you go

TOTAL SPREAD (inches)
From Field and Stream Sept 1964

YARDS
CHOKE 10 15 20 25 30 35 40

Full 9 12 16 21 26 33 40 inches

Modified 12 16 20 26 32 38 46 inches

Improved Cyl 15 20 26 32 38 44 51 inches

Cylinder 19 26 32 38 44 51 57 inches

It all depends on the gauge, the gun, and the ammo. for a 16, anywhere around 24" at 25 yards would be the norm with a 1 ounce load of shot out of a full choke. I'm talking about the entire diameter of the pattern not just the core.

Most to all patterns are made of an inner core and an outer ring of shot rapidly departing the core. Most of this outer ring of shot is made up of flattened, or disturbed shot out to about 25 yards. The core will be about 12 to 14 inches are you've seen and will contain about 90% of the shot.

Once you get to 30 yards, most of the flattened shot will have left the pattern for parts unknown. the core will have spread to about 20 inches and the disturbed shot will have begun to fill out the annular ring. However, that ring will be pretty thin and still ineffective for reliable killing.

At 35 yards, the core will still be about 20 to 22 inches in diameter, a tad thinner, and the annular ring will start to fill out enough to just start to be effective on bigger birds like pheasant. However, about 60% of the birds caught in the outer ring will be crippled and not killed outright.

Once that pattern reaches 40 yards, the core will be covering about 24 to 26 inches, well distributed in this area, and the outer ring to 30 inches will be nicely filled enough to hit and kill at least 70% of the bigger birds caught in it. About 70% of the shot will be found in this 30 inch pattern.

I've learned over the years, that given the right size shot for the game, putting the sweet spot of the pattern on the target will kill any bird it hits, 100% of the time. More open chokes develop that 20 to 24 inch sweet spot closer in. A good spreader load will throw a 24" sweet spot inside of 25 yards and won't shread the bird to pieces.

For real close work, use a minimum amount of shot or a small gauge like a 28 or .410 with fine shot like #8 for really small birds. a fast opening, hard hitting 16 ga. 3/4 ounce load of # 7 shot will dump even a good sized rooster inside 20 yards without shreading it into bird burger. So will an identical 28 ga load out of an open choke like skeet.

IC will cast a good sweet spot at 27 yards to 33 nicely with any good load. A modified choke will throw it at 30 to 36 yards, and a full at 35 to 45 yards.

A well regulated double gun will throw the centers of both sweet spots to within 2 to 3 inches of each other out to 40 yard or more. Such accuracy will allow the shooter to place either pattern center close enough on target to reliably kill any bird shot out to 45 yards. That is also why I demand that all my double guns have well regulated barrels. This kind of accuracy will offset any minor fluctuations in pattern density enough to allow the shooter to cleanly kill any bird he centers with either barrel within the limits of the choke used.

This problem of barrel regulation and accuracy is also why well made single barreled repeaters with good barrels seem to be more effective game takers out at the longer distances. This is also why repeaters are used more often for pass shooting at waterfowl. However, a properly regulated double will be just as accurate and effective. However, well regulated double guns are harder to find than some buyers assume in today's market. Learn to know one by eye and you'll be miles ahead of the uninformed buyers, as well as being on your way to becoming a deadly game shot.

Bottom line of that verbiage Very Happy

is to pattern your gun with your load at the distances you expect to shoot most of your birds (UP grouse woods alot different than a field of CRP in Western KS)

verbiage :from the Septuagent greek translation of the Hebrew OT
re: Ecclesiastes 6:11 "The more the words, the less the meaning, and how does that profit anyone?"
(OK 16gg-let's see you top that one Laughing

)

Member Joined: 15 Mar 2005 Posts: 358 Location: Houston

That one's going on my bulletin board, revdoc.

I get plenty of verbiage. It helps keep me regular.

I drove a brown verbiage in high school - the emmisions smelled like the car...

Hense the name S**T box. Laughing

I'm betting we all drove at least one of these back in those adolecent years. I drove several. My favorite was a faded light blue Dodge Dart with the old unkillable Slant Six. that car slowly disintegrated around the drive train. I fed it oil intraveniously. Laughing

I am looking for a S**t Box right now. I've come to realize that Boston commuter drivers resent new cars. They keep bouncing off them until the new car looks like a S**t box. So I'm joining the crowd.

I'm going to find a real loud yellow colored one and use orange paint to highlight all the battle damage. I'm betting the rest of the drivers will take one look and get the hell away from me. After all, a morning commute to Boston is nothing more than a one way demolition derby. Might as well look like the craziest fool on the road. I'm even thinking of wearing a Darth Vador styled crash helmet and goggles. I wonder if I should mount a pair of mock Browning 30's on the hood. "Take that Red Baron." "I have you now young Skywalker." Very Happy

You guys are great.

I was getting pretty big patterns and thought there was something wrong with the choke. Clearly I'm a shotgun newb.

By the way, I went to Wal-Mart to see if I could get some 16ga. shells and the clerk said "there's no such thing" despite my assurances to the contrary. Amazingly they had .410 on the shelf. Is the .410 now more popular than a 16? Seems hard to believe.

16GG - I'm betting we drive the same roads regularly - you north or south shore?

I had a 72 Duster - orange...and a 77 plymouth Volare wagon "Primere" - Primere means "first" in french apparently but I'm pretty sure it means "number two" in english

*Last edited by brdhnt on Mon Feb 28, 2011 5:36 am; edited 1 time in total*

RS,

Years ago I was told that a full choke should spread 1" for each yard of travel. A modified would spread 2" and an IC should spread 3". Since then I have read a number of gun writers Razz

who say that this is an old wives tale.

Kind of like measuring the length of pull from the elbow to trigger finger. Another OWT.

Gee, I've measured thousands of patterns at different ranges and the OWT is pretty close and the best LOP for me is within 1/4 inch of elbow to trigger finger. Hmmmmmmmmm?????????????? Surprised

TMB
________
Rehab forum

There just happens to be a rather informative article about this very topic in the NRA monthly American Hunter for October.

Sproket asked:
16GG - I'm betting we drive the same roads regularly - you north or south shore?

Answer: If you commute to Boston, what possible difference does it make. Its still a one way demo derby coming to or going home. It plain sucks. I refuse to drive a decent car as part of this collective rolling loony bin. From now on, my motoring handle is going to be The Kamakazi Kid---"BanZai"!!! Rolling Eyes

I wonder if the state will let me get a personalized licence plate with "BanZai" on it? Cool

Received my Oct. American Hunter yesterday and as Wildweasel said they have an article titled "Why Won't My Gun Pattern". It was the first thing I read last night. The theory of how choke works because of air resistance on the front of the shot charge and pressure on the rear from the wad is one I have never heard or read before but it does make sense. In the past all I have ever read is "nobody really knows why choke works". Great article.

Dennis

High speed, stop action video recording has pretty much settled the issue of what happens to a shot column after it leaves the barrel. The effects of varying degrees of choke can be seen too.

Choke works just the opposite of what most folks assume. An open choke or no choke allows the shot to leave the barrel in a shorter fatter, denser string. The pellets at the rear of the column draft behind the front pellets and eventually push the leaders out of the way. The slower flaring pellets then begin to fall behind and outward around the inner core of faster pellets.

As this outward and to the rear migration of pellets is happening, some random collisions are also taking place as misshapen shot meanders its way toward the outer regions of the pattern. These random collisions further cause the pattern to dispurse outward.

At the same time, the center core of shot is dispursing outward, but at a slower rate than disturbed or misshapened shot in the outer regions of the pattern. This inner core of pellets is travelling slightly faster than the pellets forming the annular ring. The same spreading action is also taking place as the pellets in the rear of the core overtake and disturb the pellets in the front of th core. This continues until there are few pellets left in the core to draft behind. Some of the core pellets will continue a relatively straight path to the mark and will remain within the central core of the pattern.

All the while, the shot is stringing out as faster pellets outrun slower ones. Finally, gravity will cause the entire pattern to fall to the ground as the pellets continue to dispurse outwards.

A full choke retards the shot at the back of the shot column and squeezes the column into a longer, more strung out stream of shot. Dispursement from the central core to the annular ring takes place at a slower rate as there is less shot in front to bump into and less to draft immmediately behind. Therefore less shot is disturbed outwards or randomly within the column.

This slower dispursement is of course happening as the shot column is travelling toward the mark. So the entire pattern remains smaller in diameter as it speeds along. It also appears to have a denser core only if it flies through a patterning sheet. Actually it is more strung out so it is less dense than it appears on paper. However, the entire column is travelling much faster than a bird or a clay target, so more shot collides with the mark if that mark or target flies through the center of the pattern.

Try to envision What I've attempted to describe. If you can, you will understand how choke works and how a shot column dispurses faster or slower according to how long or short it is.