.62 load for O buck

[flatrock]

Just wondered what would be a safe load of O buck. Using a mid weight 43 in bbl. 62 cal.

 

[wittzo]

I wouldn't use anything larger than #1 Buck with that bore diameter, it might "bridge" where two pellets try to go out the barrel next to each other and get stuck in the barrel and block the bore. Traditionally, you use the same volume of powder as shot for a shotgun load. If you use less powder, the shot spread is usually tighter, if more powder is used, the shot spreads more. I measured 18 pellets of #1(the equivalent of a Buck load for a 20 gauge BP shotgun) with my powder measure and it's about 80 grains, so load it over 80 grains of BP.

40 grains of BP works well in my .638" Howdah pistol and 80 over 80 works phenomenally well with my .69 smoothbore. With a .62, you can use larger buckshot, like OO and OOO, they shouldn't bridge, but you won't get an efficient package with that bore, which is between a 20 and a 16 gauge, and they will be more deformed from stacking. You can also mix smaller buckshot or even large birdshot to make a "duplex" load so the smaller pellets fill in the gaps between the larger pellets and really pack a punch, depending on what you're shooting.

 

[tg]

I try to match the weight of the heaviest connical I can find for the caliber and use no more than that weight in combined shot weight.

 

[CoyoteJoe]

In choosing buckshot you can be guided by what the ammo makers load in modern shotshells. To give an effective pattern and not be badly deformed the pellets must sit in layers, not a jumbled pile. Number 2 buck is the largest size they load in 20 gauge because that is the largest that will layer in the bore. Twenty gauge is really just a bit small for buckshot, the 16 has a big edge there with "0" buck and of course 12 gauge can handle anything from #4 to 000.

 

[flatrock]

Many thanks for the replys. I guess I just wondered if anyone had tried it. I think I`ll just stick to conventional sizes. I think I`ll try to find me a mold. What size would be right for the .62?
I`ll probably use it with a patch.

 

[paulvallandigham]

Are you asking about a mold for round ball, or for buckshot, still? :idunno:

 

[flatrock]

Paul, I was thinking about a mold for round ball. I just wondered what is the most used for a .62 cal. I will probably use it as a patched round ball. I have a .50 cal smooth bore and use it with PRB. and the usual # 5 and #6 shot. I use a .490 in the .50. I live in the Valley of the Cumberland River in Mid TN. And have just recently started using a Smoothie. It seems to be easier on 74 year eyes! I started with my first ML rifle at age 16. I have really enjoyed the transition to Smoothbores but still use my rifle a lot.

 

[paulvallandigham]

The most common MOLD for a RB for a 20 gauge, or .62 caliber smoothbore would be the .600" diameter. However, some barrels are larger, and you can use a .61`0" diameter RB, and some bores are tighter, and require a drop in diameter to .595", or even .580".

Nominal diameter on the 20 ga. smoothbore is .615", but there are all kinds of bore sizes being sold as "20 Gauge". Its very important that you measure the ACTUAL diameter of your smoothbore( or any rifle for that matter) to KNOW exactly what diameter RBs you will need.

Because a smoothbore does not have the grooves in it that rifling does, you need to be much more accurate in choosing the THICKNESS of the patching material you use in them. Any cotton or muslin patching material will compress somewhat below its measure thickness in your hand. However, it can't compress as much as it would being used to shoot the same ball out of a rifle of the same caliber.

You want the ball to be at least .015" Smaller in diameter than your bore diameter, and you want to see which thickness of patching material works best for accuracy. If your bore diameter runs from .615-.620, then try the .600" balls, and use a .015, .018, or .020" thick patching material. See which works best for you. Expect there to be some variation in the diameter of any cast RB, and there can be variations even in swaged RBs. For the most part, you are looking for a Ball/ Patch combination that can be "thumb-started" down the muzzle of your fowler. :hatsoff:

 

[Joel/Calgary]

I wouldn't use anything larger than #1 Buck with that bore diameter, it might "bridge" where two pellets try to go out the barrel next to each other and get stuck in the barrel and block the bore.

For those who have not seen it before, the proportions between the diameter of buckshot that would sit in even layers and the diameter of your bore (or the minimum of your choke, or inside the shotcup, or inside the shotcup passing through your choke, etc.) are:

- - - - - - - - - - - - - - - - - - - - - - - - - - -
buckshot size for loading in even layers:
- 2: 1/2 * the minimun diameter of bore, choke, or inside of shotcup
- 3: .4639 * the minimum diameter "
- 4: .4142 * the minimum diameter "
- 5(+1 in centre between layers): .36± * the minimum diameter "
- 7: 1/3 * the minimum diameter "
- - - - - - - - - - - - - - - - - - - - - - - - - - -

I suspect that normally, one would use something a hair smaller than the "exact fit" size to allow for imperfections, fouling, etc. I've never seen anyone calculate for layers of more than 7 - probably by then, one can just treat them as loose shot.

I measured 18 pellets of #1(the equivalent of a Buck load for a 20 gauge BP shotgun) with my powder measure and it's about 80 grains, so load it over 80 grains of BP.

With respect, something sounds odd. By the numbers I have, 18 pellets of #1 buck should be around 1.5/8oz, and ought to fill something like a 120gr powder measure. An 80gr powder measure ought to hold around 1.1/8 - 1.1/4 ounce of shot.

Plus, the larger the ratio of the shot size to the diameter of the measure, the less well it packs. If you check the same weight of smaller shot, you should get a smaller volume.

Regards,
Joel

 

[paulab]

greetings.....Just an opinion here. When I was skinning out the last 5 deer taken in Michigan's thumb, [shotgun/muzzleloader zone]I found that 3 of them had OO buckshot lodged just under the skin. That is proof enough for me that buckshot is a lousy thing to use on deer. I would rather MISS than pepper one with buckshot. Just my opinion but backed up by FACT! cheers Paul

 

[wittzo]

Let me check my "recipe" I was going on memory about the buckshot...and I already suspect I was in err..

Aha..12 pellets of #1, not 18. It's a double barreled pistol with .638" bore diameter at the muzzle. I used the Pedersoli's Howdah starter load as a beginning and used 20 gauge shells as a reference. I took 12 pellets, weighed them, then took an equal weight of #7 birdshot and measured it's volume, but I still used less powder when I loaded it. It's been a while since I have loaded it with buckshot, mostly using #7 or solid balls (.60")

I figured that smaller birdshot is more dense than roundballs or buckshot, the shot fills in the holes with more lead, less air.

 

[Joel/Calgary]

Nicely done - we're on the same page, with one exception.

I figured that smaller birdshot is more dense than roundballs or buckshot, the shot fills in the holes with more lead, less air.

Actually, in bulk, small shot and large shot (of uniform diameter, not mixed sizes) of the same alloy will have the same average density. The difference we observe in measures comes from the edges. I'm a slow typist, so I've copied & pasted something I wrote in a previous discussion.

Regards,
Joel


How much shot a measure will hold depends on the aggregate density of the shot - for lead (and its alloys), it's usually given as approximately 7 times denser than the powder, depending somewhat on the alloy. This is apparently the density of hexagonally-close-packed uniform spheres composed of lead alloys with bulk densities of 10.75-11.25 g/cc, depending on alloy, and is independent of shot size (36% porosity, IIRC). That should calculate to 6.9-7.2 g/cc, with most shot alloys in the 7.1-7.2 range. All comparisons I've seen of shot and powder in real-world measures actually come out with shot less than 7 times the weight of the powder because the shot are not perfectly packed in the measure. The dimensions of the measure STRONGLY affect how much shot actually fits in - especially with larger shot. Because of the effects of the geometry of the shot against the sides of the measure, larger shot will not pack as well as smaller, so it will weigh even less in a given measure, and the smaller the diameter of the measure, the greater will be the effects of shot size on charge weight. (I've heard this called "boundary effect" in a discussion of packing.) A shot measure is comparatively fat to minimize the boundary effects on packing and be more consistent with different sizes of shot but with some loss in precision, while a powder measure is skinny to allow more precise measurement of the much finer gunpowder because the boundary-effect differences are much less among different granulations of powder.

Picture a layer of shot in the measure. In the middle, the shot is likely close to that perfectly ordered hexagonal packing, but around the edge, there will be places too small for a shot to fit, so there is less shot in the layer than a perfect hexagon of the same cross-section, or, alternatively, of a circle drawn over a wide perfect layer of hexagonally packed shot. The larger the cross-section of the measure compared to the size of the shot, the greater the portion of the area that will have shot in dense hexagonal packing (roughly proportional to the area of the measure, or to the diameter squared) and the smaller the portion with some "missing" shot (roughly proportional to the circumference, or to the diameter [directly, not squared]). Similarly, the larger the shot, the wider the boundary region with some "missing" shot for a given diameter of measure, and the lower the weight for that layer. The actual 3-dimensional geometry is more complicated, but the same principles still apply.