Sprue up..Sprue down

D

Doc Hoy

New member
Folks,

I am a revolver only shooter. Never shoot single-shot anything. Everything I have ever read says the ball should be loaded with the sprue up. (Forward, in the direction of bullet travel once fired.) I have always done it this way but only because:

1) I never thought about it enough to question conventional wisdom.

2) I never shot around anyone else and so was never exposed to an alternate philosophy.

3) I have not honed my shooting technique to the point where I can detect the difference.

What does the data tell us about it?

What does your collective experience tell us about it?

Have I perhaps missed a large volume of literature that holds that the ball should be loaded with the sprue down?

When will I stop asking these impertinent questions?

Tnx,
 
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Sprue up and centered that is observable on round ball. Actually, you will find that a round ball is very forgiving and makes little or no difference and yet there are many folks who are bothered by it. If you are trying to be consistant then do it the exact same way every time. With the spue down, how can you observe it's center position? ... ;)

Have you tested this to see what works best for you?


Be Safe !!!
 
Haven't tested it.

Pahoo,

Yes...Hard to see where the sprue is if it is facing the cap end. Maybe that is the rationale for the guidance from experts.

I haven't tested it but in all fairness I really should start with that. I am working on getting consistent results from my casting process. (Ball size and ball weight) and trying to match that to accuracy. So I am pretty careful about making sure the sprue is pointing toward the foc'sle.

It is gratifying to read in your post that round balls are forgiving when it comes to the orientation of the sprue. To me, this means that round balls are forgiving of changes in other variables as well.

You can see that there is alot about the science of shooting that interests me but with which I am not yet familiar.

It sure is fun learning.
 
Just don't put it to the side. While it may shear all of it off it may leave a gap and increase odds of a chain fire. I've done it both ways and can't tell any difference but I didn't try to be scientific about it. Conventional wisdom would put the sprue forward because ballistically any deformity in the front of a bullet has less effect than a deformity in the rear.
 
So I am pretty careful about making sure the sprue is pointing toward the foc'sle.
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As opposed to the FanTail .... ;)
You speak my language, Sailor

To me, this means that round balls are forgiving of changes in other variables as well.
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Absolutely!! After my first run, I probably reject about a third and when I'm really picky, I shoot the bought ones but then again, this is not as much fun as shooting your run. However, don't change your method cause it sounds like you are doing well and having fun and that's the best part.

Be Safe !!!
 
If they are still making those swaged balls without sprues since they are not cast(?) maybe buy some of those as they are nothing more than lead marbles and you could apparently put them in any whicha way. Or cast bullets, instead of balls, and those are very apparent which end goes which way.
 
Sprue up, sprue down, decisions, decisions, wow you guys are getting too technical, no wonder some are using inliners, drop in a coupla pellets ram in a regular bullet and touch it off with a primer that can start a forest fire.:D

Sprue up
 
Conventional wisdom would put the sprue forward because ballistically any deformity in the front of a bullet has less effect than a deformity in the rear
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I have always loaded sprue up because I don't want the sprue near the area that shaves the ring of lead.

Not to be argumentative Hawg, I'll buy the first round and we can discuss this.
I would think any deformity in the front of the ball well have more of a effect than if it's at the rear. This seems to be the conventional wisdom of the long range crowd. The bullet has to move the air molecules apart to pass through the air. A smooth surface is more efficient at this than a deformed surface. Any deformity would induce a certain amount of drag.
 
It's absolutely true that departures from a perfect spherical shape matter aerodynamically, but we're talking secondary effects here in any case. There are other variables that are more important, such as consistency in compressing the powder, the amount of powder, etc. It's not clear, but empirically seems likely that we lack the ability to measure the effect of sprue placement in terms of accuracy due to it's secondary nature. At least, the majority of experience expressed in this and other threads would seem to indicate that.

As to whether the aerodynamic (not ballistic) effects of the sprue deformity are greater with it at the front or rear, my experience with the theory and experiments with spheres in the airstream as an undergraduate aerodynamicist some 40 years ago suggest there is little if any difference. The main issue is where, when and how violently the laminar boundary layer flow detaches and then reattaches as a turbulent boundary layer. While it may seem to common sense that the sprue facing the airstream would cause that to happen sooner, at lower Reynolds numbers, that isn't necessarily so. It's also possible that, in a less than perfect ambient airstream (perfect being fully parallel streamlines) any detachment caused by the sprue might immediately reattach away from the sprue, negating the drag increase.

At any rate, this stuff is for aerodynamic theory students. I don't believe we can reliably measure the effect in the real world or the statistics would exist. In the end, my decision will be based on obtaining the best chain fire insurance, which means knowing the sprue is not contributing to a gap that might allow some hot gas to reach the powder.
 
Madcrate has it right

True story. And yes, I'm braggin'

20+ years ago I shot a 25yd. 50 round slow fire match with a Navy Arms 1860 using 452460's. They would not load in through the barrel cut-out of course, so I used a pair of diagonal cut pliers to cut off the rear grease groove. It gave the bullet a 'v' shaped base.

Holding 10" low at the bottom of paper, I won the match over K-22's and 38's. I also had the high X count. Claims were made that my powder smoke caused their scores to suffer. I just think they didn't like having me take so long to finish, but there was no time limit stipulation.

Bullet base just did not factor in, at least to 25 yds. I have always loaded roundballs sprues up.

A rock tumbler also works to pound them in, saving the trouble of orientating them.

JT
 
Mykeal and JT

JT first.

I like to go to yard sales on saturday mornings with my wife. Went out this morning and a guy had a rock tumbler for sale. I came within a nanosecond of buying the darned thing for just the reason you mentioned. I have heard of tumbling cases for cleaning (I am not a cardtridge shooter by any stretch and so anything that has to do with cartridges is a mystery to me).

Anyway, I let it go because he wanted a little too much for it. But if you have some good experiences with tumbling bullets, I would be happy to know about it. This is probably one of the areas in I would be far better informed if I would just join a club and shoot with some humans.

To Mykeal,

I had a situation come up with my ROA. At 25 gr. the loading lever bottoms out on the frame of the pistol. I don't use corn meal because I have wanted to avoid adding yet another variable. I must say that the fact that the geometry of the pistol prevents me from applying all the desired pressure on the load is a little disconcerting. I can feel the powder begin to compress but the compression is less than I am comfortable with on the Colts and Remingtons. At least I know that the compression is essentially equal from chamber to chamber (I use a CVA A1400 measure and I am relatively confident that my powder loads are consistent in volume.)

As you say it is nearly impossible to judge with accuracy the amount of pressure I am using with the loading lever. I would estimate that it is not much less than it takes to get the ball to begin moving into the chamber. (.457s in the ROA and .454s in other pistols) But this certainly is not the case with the ROA, since the loading lever bottoms out before the resistance rises very much.

I wonder if I am trying to compress too much in my Colts and Remingtons?!

I will begin to use corn meal, but not yet.
 
In front stuffer single shots, I always load with the spru up - that's the way I was taught by an old long time mountainman and muzzleloader. He said if you loaded the gun with the spru touching the barrel (on the side), it casued a tight spot through the patch and into the grooves that would throw the shot off. I never had any reason to doubt what he said.

In revolvers, I don't pay much attention to where the spru or flat is. Since there is a ring cut on loading, or the ball is compressed and fills the chamber, I don't see what difference it makes - and I always use lubed wads, so chainfires arent a concern.

FM
 
Not to be argumentative Hawg, I'll buy the first round and we can discuss this.
I would think any deformity in the front of the ball well have more of a effect than if it's at the rear. This seems to be the conventional wisdom of the long range crowd.
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I'm mostly going on memory of discussions on reloading/casting forums that most people didn't like molds that poured bullets base up so the sprue was on the bottom. They wanted molds that poured nose up so the sprue would be out front. I dunno. Like I said I've done it both ways and can't see any difference.
 
In the last few months I have started to run my home-cast RBs in my case tumbler. It is one of the Midway plastic bowl ones. I empty the bowl of media & put a batch of balls in there......50 to 100 depending on caliber. Run the tumbler for 20-30 minutes & the sprue is gone & they closely resemble the factory swaged balls.
 
Doc Hoy said:
I wonder if I am trying to compress too much in my Colts and Remingtons?!
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With respect to real black powder only (the synthetics are a horse of a different color):
In my experience compression is important for two reasons:

1) it ensures the ball is seated on the powder, meaning there is no significant air gap between the powder and the ball. This requirement (and it is a requirement) can also be effectively met using an inert filler or wad.

2) it adds the ability to ensure consistency in the loading process. By that I mean if you concentrate on compressing the powder a certain amount each time you are more consistent in your procedure each time.

I don't believe the amount of compression (given that you ensure the ball is seated firmly) is nearly as important as doing the same amount each time with any given gun. It's a fact that the amount of compression will affect the rise time and perhaps even the maximum pressure reached in the chamber, but that's affected by many other variables as well, some of which we have no control over. The physics are that compression alters the air space between the granules and thus the amount of free oxygen that can participate in the burn process; but whether any given amount of free oxygen helps or hinders the process is not fully understood. Further complicating the issue is whether you can really control the amount of free oxygen with compression. You can and do AFFECT it, but can you really CONTROL it? That's not clear to me.

Are you trying to compress too much? Probably, but it's hard to be sure. Seat the ball on the powder firmly, using all the leverage the loading lever can provide. If your hand hurts, that's too much. I lower the lever and ensure it's centered on the ball. I then use a good, firm stroke to cleanly swage the ring off the ball and drive it into the chamber. When I feel it hit the powder, I push firmly to ensure it won't move any more and then remove the plunger.
 
Here is a thought

Mykeal,

As it is now (with my present shooting habits) getting absolutely consistent compression in each chamber is not so terribly important, but if it became important I think I might do a minor addition on a table loader. I don't presently use one but I am thinking of the addition of a sort of ruler mounted in a vertical position against which the lever could be measured. In my mind I can imagine myself saying, "For X pistol, with X ball and with X amount of powder, I always push the level down until it meets the ruler at the 3 inch mark." With such a device, one could actually expirement with different compressions. It would be an easy addition to make. In fact, I am guess that it may already have been tried and abandoned as not a viable way of getting consistent compression.

Thoughts anyone?
 
It would be interesting data, to be sure. The experiment would be fun, but it sounds like a bit too much effort for everyday shooting.
 
Doc, you should look at the Triple P loader. Manufactured by a member here, it has an adjustable stop on the ram so you can have precise compression chamber to chamber. I played around with it a bit, working at keeping the compression as consistent as I could. It did seem to help accuracy, but would really need a shooting vise to really know for sure.
 
The Bevel Brothers (Muzzle Blasts magazine) did an article several years ago about sprue up and down. After some tests, they determined it made no difference. Remember, the riflemen of the old cut off the sprue with their knife and returned the sprue to the melting pot.

They were supposed to be legendary marksmen, but I suspect that some exaggeration is involved. Their rifle balls must have varied in weight because of the practice of cutting the sprue. I don't think they can be as accurate as some of our shooters today who meticulously measure every ball for its weight.
 
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