I keep hearing people on the boards explaining that the Nitro with the 2 7/16 oz load (or whatever heavy load shell someone is using compared to a lighter load) has to be shot through a larger diameter choke tube because it's just too big a load to shoot through the tightest chokes. Supposedly the 2 1/4 oz will pattern better through the tight choke.
Well, I'm not sure I understand the reasoning here. We're not shooting a 10 gauge shell through a 12 gauge gun. We're shooting a 12 gauge shell. The super heavy loads of shot are the same diameter as the smaller loads of shot. If the choke is a .660" then the diameter of the load (shot still inside the wad) is .660" in diameter until it leaves the front end of the choke. The length of the shot/pellet combo should not change the diameter of the combo. And lets face it, you're only going to get so many shot and wad to go through the choke at once. It just takes a little longer for the heaviest loads to get out of the choke. I can see how it would be effected by a back bored barrel like an 835 because the shot/wad load is able to expand more in the larger diameter barrel and choke. Choke diameter is not the only factor in determining the tightness of the pattern. Choke is a relative measurement. It is the percentage of constriction compared to the inside diameter of the barrel. That's why we don't shoot a .643" SSX in a Mosberg 835.
I'm not arguing that the 2 1/4 oz load won't out pattern the 2 7/16 oz load.I believe there are other factors than weight of shot charge at work here but I don't know what they are. Maybe it's a different wad length or pressure to get the extra 3/16 oz of shot in the same shell. Maybe it's the powder charge.
I'm always open to learn new things.
Slick I'm gonna have to call a big B. S. on you bud. Computation fluid dynamics has no corelation what so ever with internal or external ballistics. Plus you want to change "pipe" sizes on me. We're shooting both these loads through the same barrel. Theoretically the only thing we're changing here is the length, not width, of the shot column. That should not effect the efficiency of the choke. Of course that's just my opinion and I could be wrong.
Here is what I think happens. I can't proove this and I know of no way to measure the internal pressure that occurs inside of a choke, but it has always seemed logical to me.
As the quantity of shot inside a given shell increases the internal pressure in the choke and the pressure applied to the shot goes up. No the diameter of the shot collumn does not increase because you put more shot in the shell, the length of the shot collumn in the shell increases. But something different happens in the choke than what happens in the shell. As the front edge of the shot collumn enters the constriction of the choke and constriction is applied, it slows the leading edge down. The shot behind it catch up and "stack up" in the choke as the shot collumn length shrinks a bit. The more shot in the collumn the greater this stacking effect will occure and pressure will increase. We know that too restrictive a choke will blow a pattern due to excessive internal pressure applied to the shot and then suddenly released as the shot exits the choke. Therefore a lighter load may make low enough pressure in the choke to give a good pattern, but increasing the amount of shot will increase the pressure in the choke due to the stacking effect to the point that the pattern will be blown. The solution is to use a less restrictive choke as the quantity of shot is increased.
Skeeter
You bring up a good point about the shot compressing with a heavier load. That might have something to do with it. On the other hand, when the primer sets off the powder the pressure jumps to 14,000 psi in a split second and the shot goes from 0 to 800 mph in that same split second. I don't know how many Gs that it but I'd think that shot was pretty well compressed before it ever got to the choke, whatever the weight of shot. Have you ever noticed the dents in the bottom of a wad.
And as far as comparing a 12 ga. to a 10 ga., that's almost like comparing apples and oranges. You can't compare two different gauges unless you compare percentages. Percentage of decrease in bore diameter for each choke measurement as well as percentage of change of payload for the lighter loads to the heavier loads. And the chamber pressures between the gauges is so different, with the 3 1/2" 12 ga. being the hightest pressure of any of the gauges. This might also explain why the Super Mag kicks the begeebers out of me.
Here's a chart I just Google'd about chamber pressures. Take it for what it's worth. All my data comes off the internet and you know how much faith you can put in stuff on the internet. Hey, they even let me post stuff on here. I'm just saying.........
Shotgun Pressure Specifications
SAAMI Shotgun Pressure Specifications
Shotshell Maximum Average Pressure (MAP) in PSI
10 gauge 11,000
12 gauge 11,500 (except 3-1/2 in.)
12 gauge 3 1/2 in.14,000
16 gauge 11,500
20 Gauge 12,000
28 gauge 12,500
.410 Bore 2 1/2 in. 12,500
.410 Bore 3 in. 13,500
(With the pressure of the 3 1/2 12 ga. and the 3" .410 being so close together, I wonder if a man could expect some correlation between the two.)
All i know is i shoot a 870 with a 660 JH and the h517t nitros 4x5x7 and got 354 in the 10" circle at 40 yards. That is a 2 7/16 ounce load. I doubt a 670 would have did better :you_rock: :you_rock:
:icon_thumright: :icon_thumright:
thats an incredible pattern, is that one of your handloads slicky??
Quote from: slickyboyboo on March 23, 2011, 05:14:06 PM
Quote from: HOOK KILLER on March 23, 2011, 04:52:49 PM
All i know is i shoot a 870 with a 660 JH and the h517t nitros 4x5x7 and got 354 in the 10" circle at 40 yards. That is a 2 7/16 ounce load. I doubt a 670 would have did better :you_rock: :you_rock:
870 SM - 40 yds I'm sure a .680 would have done better than that.
(http://img91.imageshack.us/img91/4337/imagelc.jpg)
he was shooting 4x5x7 and you are shooting 7's so naturally you already have more pellets starting out so you should have more hits. the only comparison would be to shoot 4x5x7 out of your 670 and thn post the pattern
he was shooting 4x5x7 and you are shooting 7's so naturally you already have more pellets starting out so you should have more hits. the only comparison would be to shoot 4x5x7 out of your 670 and thn post the pattern
:agreed:
Hook Killer
You're giving me hope here. Besides the 870 SM and the Jelly Head is there anything else you're using or doing to help you get that good a pattern?
Quote from: Nimrodmar10 on March 23, 2011, 09:18:52 PM
Hook Killer
You're giving me hope here. Besides the 870 SM and the Jelly Head is there anything else you're using or doing to help you get that good a pattern?
Slicky is shooting strait 7's and his recipe of handloads so according to my calculations if I shot strait 7's my pattern would probaly be better than his :help:. There is no way to know though until you compare apples to apples. Anyways, I shoot a dirty never been polished 21" barrel and the H517 nitros 4x5x7 out of a .660 JH. I have never tried a different choke so I cant comment on what would work better but I am satisfied with what i have :anim_65:
Quote from: slickyboyboo on March 24, 2011, 09:18:55 AM
Quote from: snapper1982 on March 23, 2011, 08:47:31 PM
Quote from: slickyboyboo on March 23, 2011, 05:14:06 PM
Quote from: HOOK KILLER on March 23, 2011, 04:52:49 PM
All i know is i shoot a 870 with a 660 JH and the h517t nitros 4x5x7 and got 354 in the 10" circle at 40 yards. That is a 2 7/16 ounce load. I doubt a 670 would have did better :you_rock: :you_rock:
870 SM - 40 yds I'm sure a .680 would have done better than that.
(http://img91.imageshack.us/img91/4337/imagelc.jpg)
he was shooting 4x5x7 and you are shooting 7's so naturally you already have more pellets starting out so you should have more hits. the only comparison would be to shoot 4x5x7 out of your 670 and thn post the pattern
I guarantee that the nitro 4x5x7s have more pellets than my straight #7s. The #4s and #5s make up a ver small portion of the shot in one of those shells, and they are loaded to the gill with what refer to as #7s (actually #7.5s as are mine). The only difference is mine are uniform in size, because I sorted them that way, and Nitro doesn't, therefore they have plenty of subsized pellets ranging #7.5s, #8s, #9s, and even #10s therefore their numbers are boosted substantially. If anyone begs to differ, cut one open yourself and look.
i was just making a point that the only way to compare is not from different guns and different chokes but rather form the same gun and choke with different loads. i doubt with the price of them that i will cut one open. i think i will take your word for it.
Quote from: slickyboyboo on March 24, 2011, 09:44:43 AM
Quote from: HOOK KILLER on March 24, 2011, 09:12:40 AM
Quote from: Nimrodmar10 on March 23, 2011, 09:18:52 PM
Hook Killer
You're giving me hope here. Besides the 870 SM and the Jelly Head is there anything else you're using or doing to help you get that good a pattern?
Slicky is shooting strait 7's and his recipe of handloads so according to my calculations if I shot strait 7's my pattern would probaly be better than his :help:. There is no way to know though until you compare apples to apples. Anyways, I shoot a dirty never been polished 21" barrel and the H517 nitros 4x5x7 out of a .660 JH. I have never tried a different choke so I cant comment on what would work better but I am satisfied with what i have :anim_65:
So where are your pattern pics of the 354?
Someone tell me how to post pics and i will. I have never done this before on here or had any one to question me for that matter. someone please inform me how to do this and i would be more than happy to
Slick
I've counted the pellets several times in a Nitro 2 7/16 oz load of 4-5-7s and there's always right around 550 pellets unless some of them are completely missing the 4'x4' pattern targets I use. According to the chart you posted earlier there are 619 pellets in a 2 7/16 oz load of #7 and 722 pellets in a 2 7/16 oz load of 7.5s which is what you say you shoot. I'd say that a person would have a very good chance of getting a better pellet count in a 10" circle shooting 722 pellets in a load instead of 550.
Do you perchance have some patterns with the Nitro 2 7/16 oz of 4,5,7s and the Nitro 2 1/4 oz load of 4,5,7s fired through the same shotgun with both a .660" and .670" of the same brand and type choke? I'd be curious exactly what difference the choke diameter has when all other things are equal. Or if someone else has the patterns I'd like to see them. I'm betting Clark Bush probably does.
Quote from: slickyboyboo on March 24, 2011, 12:58:27 PM
I've never counted a Nitro 2 1/4 oz 4x5x7 shell that has had that few pellets, most were in the 700+ range. There were a few folks on the old site that had taken apart some nitros and dissected them, I don't remember what their counts were, but I do remember there were a ton of subsized pellets.
Yeah, I keep hearing that old saw about the "tiny" pellets in the Nitro loads. I've just never seen it in the 3-4 years I've been shooting them. I think that rumor is like the one that won't go away about the square Hevi-Shot pellets. Granted, the early cast shot left a lot to be disired but things have changed.
Folks should read Clark Bush's interview with Jay Menefee. Mr. Menefee started Polywad Corp. and according to the interview: "the man who perfected and loaded the 12 gauge "Old White" Hevi-13 shotshells that set so many NWTF Still Target Shooting World Records and are still highly sought after some 5 years after production of them ceased." Mr. Menefee says: "Environ-Metal designed a special shot grading machine, had it built and shipped to our shop. They would ship barrels of shot to us and we'd use that machine to sort the shot". This is a very good interview. I hope Clark doesn't mind if I post a link to it here. http://allaboutshooting.com/article_info.php?articles_id=433
Come on folks, would we still be paying over $7 a shell if the Nitros were shooting "dust"? And if anyone has any of those Nitro 2 7/16 oz loads of 4,5,7s that have 700+ pellets in them, I would like to buy them.
someone pm me with your email address and i will send you my pattern pics to post. I am kind of busy at the moment and dont have time to do all the steps with the photo bucket
It actually does have to do with flow IMO.
My theory is the heavier shot charge takes up more space thus leaving less room for buffer. The smaller shot charge takes up less space and leaves more room for buffer. The buffer allows the shot to flow. Less buffer=inhibited flow=more resistance=less efficiency. To lower the resistance of the heavier load one needs to increase the ED when speaking of the same choke design.
This is the same principle when moving to larger shot sizes. Larger shot=more resistance, to lower the resistance one needs a larger ED in the same design choke. An example: My 2-1/4oz hevi 6 handloads perform much better in a JH 665 vs a JH660. Tried it in several guns with diff EDs of the same choke design, even two of each ED of the same brand chokes and the results were the same.
This is commonly known as "over choking" to most.
I once took a light shot charge and increased the buffer amount to take up the space. These were lower MV loads. Comparing the higher buffer loads to the same loads with less buffer was an amazing difference.
When referring to the Nitro 2-7/16 loads, there's not a hull with enough capacity to increase the efficiency of the loads by adding buffer to lower the resistance in smaller EDs of the same design, so your only efficiency gains come from lowering resistance by going to a more open choke. That said, I don't personally feel you would ever get a good balance in efficiency from the choke alone thus the heavier payload will remain less efficient.
When loading your own, you can really get a grasp of what it takes to increase efficiency. So much so that some loads become entirely too efficient. I try to build the load to achieve the highest efficiency, then I tinker with chokes to bring the efficiency to a level I feel comfortable with for hunting.
That's my theory on the matter, hopefully it makes sense.
Have a good one,
Reloader
I dont disagree with anyone's theroy I just know what my gum will do and I am happy with it. I think the shorter barrel has something to do with the 660. working good in my gun. I sent the pics to you slicky. Thanks for posting them
Thanks sicky. I got the POA fixed with a burris fastfire 2 so I should be ready to go now. I am wondering if polishing the barrel will help any or not. Seems like alot of work when I already have awesome patterns. Any input?
Quote from: slickyboyboo on March 25, 2011, 09:07:57 AM
Quote from: HOOK KILLER on March 25, 2011, 08:33:36 AM
Thanks sicky. I got the POA fixed with a burris fastfire 2 so I should be ready to go now. I am wondering if polishing the barrel will help any or not. Seems like alot of work when I already have awesome patterns. Any input?
If you are consistently getting those numbers at a true 40 yds, I wouldn't worry about a thing!
That is what i thought also :z-guntootsmiley: :z-guntootsmiley:
Thanks Reloader. The buffer is something I haven't ever considered. Just didn't think of it. I've never cut open an unfired Nitro, do they have buffer in them? That's something you can't see on a pattern sheet. I'm still not convinced I can't get a better pattern out of the H517Ts. Especially with the patterns Hook Killer is getting. I've shot the Rhino .660" in a 21" 11-87 with the 2 oz. load of 4,5,7s and a 26" 870 SM with the 2 7/16 oz loads. They both pattern better than the Mag Blends but not near the numbers Hook Killer is getting. I guess I'm going to have to try a Jelly Head.
Yes, they have buffer in them. I feel like you would like the 2-1/4oz loads more than the 2-7/16, but every gun is different. I would go straight 7s as well, the 4x5 part of those shells is mere marketing as the 7s are doing the work.
I like the 4,5,7 Load because the heavier 4s and 5s seem to drop into the body and break the body down annd the 7s stay in the head/neck area. I
I didn't think you shot the $7 shells Slick. :lol:
Let me ask you a question. If I've got my scope set right and my pattern centers where the crosshairs cross and if I aim at the junction of the red neck and feathers, where do the 4s and 5s in the bottom of the pattern hit the bird, in the head or the body. Unless he ducks his head, they'll hit him in the body. Now do you think a #7 pellet does as good a job of breaking large bones as a 4 or 5? And if I've got twice as many 7s as I do 4s and 5s I'm guessing most of the pellets that him him in the head and neck will be #7s. Unfortunately a lot of the #7s that hit him in the body never penetrate the feathers. A lot of them shake out on the tailgate when I put him in the truck.
The slickster is right.
I would rather just have all 7's than the 4's or 5's.
7's don't just shake out of a turkey either. I know better.
http://oldgobbler.com/Forum/index.php/topic,1421.0.html
What's shaking out of him is the #8s and #9s nitro uses