No. 1 with a Bullet

Increasing Accuracy with Blackpowder Arms

Part of Civil War @ Charleston Website

Summary- Black powder specialist and marksman Tony Beck gives pointers on improving the accuracy of the black powder musket on the target shooting range.

Contents:

• Hard lead
• Bullet Selection
• Rifling
• Barrel Adjustments
• Powder Charge

You mention that your musket does not shoot too well. Here are a couple of suggestions that might get it working better. You don’t mention if it is an original or repro, so I’ll make some comments on both.

By far the most common problem with shooting muskets today is caused by the use of hard lead to cast bullets. It is absolutely necessary to use pure soft lead. If you can not squeeze the bullet base out of round with your thumb and index finger, it won’t expand enough to take the rifling. Backstop lead from the range is guaranteed to be too hard, as is wheel weight. If there is a good plumbing supply place nearby, get some plumbers lead (not solder) from them. It generally runs about $1.25 a pound. If it is not dark gray or blue, it probably has tin in it and will be too hard to shoot. The other option is to order some lead from McMaster-Carr, (404-346-7000). Order No. 9031K1 for a 5 lb. brick. If you are buying bullets, that is no guarantee, most are cast as souvenirs and are too hard to shoot.

Another problem with some of the newer reproduction muskets is that the rifling twist is quite slow, ranging around 1 in 78 or more. They won’t stabilize the longer bullets, like the Rapine International, Lyman 577213 or RCBS 577-500. To be safe, use a Rapine or Lyman 460 grain Old Style or the Rapine 315 grain semi-wadcutter. The lighter bullet really drops dead past 100 yards but has almost no recoil and is wonderfully accurate at the shorter ranges. Either of these will shoot much better in a slow twist and will still do reasonably well with the faster 1-72 original twist. The original twist rate was very carefully chosen after a lot of testing when the service caliber was reduced in 1856. It is the slowest rate that would reliably stabilize the service bullet. This was done in order to reduce gyroscopically induced horizontal drift at ranges over 500 yards. Shorter (i.e. more naturally stable) bullets are a must with slower twist rates. Size to about .001 under the land diameter of the barrel. If you are careful in mold size selection, unsized bullets will shoot just fine. (Rapine molds are available from S&S Firearms in N.Y., ph. 718-497-1100)

On the subject of barrels, there are more than a few reproductions with very shallow rifling, less than .005 . It is difficult to get these to shoot really well. Original barrels look like they have rifling this shallow, but they are actually choke rifled . The grooves at the breech are .015 deep and taper down to .005 at the muzzle. This makes all the difference! Any gas cutting that occurs at ignition, before the bullet fully expands, is swaged out as it travels down the barrel. The only reproduction that has this wonderful feature is the (now out of production) Parker Hale Enfield. I’ve heard that the new Colts are choke rifled, but that is only a rumor. With constant depth rifling, the grooves should be at least .006 deep, .007 to .010 is better. If you really want to shoot your musket and it has a shallow groove barrel, replace it with a Whitacre barrel from S&S. They cost about $275, but are choke rifled and every bit as good as an original. Needless to say, choke rifled barrels won’t shoot patched round balls worth a hoot!

There are two subtle problems common to both originals and reproductions. First, the barrel bands must be a little loose in order to get the best accuracy. If you have the clamping type bands, loosen the screws. If they are the solid type, be sure that they aren’t too tight against the wood. Shave the stock down if necessary. Second, the barrel tang must be solidly clamped into the stock by its screw. To check this, remove the bands and tighten the tang screw. If the muzzle lifts out of the stock as the screw is tightened, accuracy will be poor. Get some 1/64 birch plywood from the local hobby shop and make shims for under the tang. It may take only one, or several might be required. The muzzle should rest in the stock with the tang screw tight when you are finished. This is a commonly overlooked musket tuning trick..

As to powder charges, start with about 40 grains of GOEX FFF, or 45 Grains of Elephant FFF for the old style bullet. This will chronograph at about 1000 fps. You don’t want to go much over this unless you have a fast twist barrel (1 in 66 or 1 in 48). Try 35 grains of FFF for the semi-wadcutter. Lube with Bore Butter or similar black powder lube. A really good lube can be easily made by melting together equal parts Bore Butter pistol lube and bees wax. Do not us a sizing lube for smokeless powder, especially if it has ALOX in it. It mucks up the barrel something awful. After only a few shots it may be impossible to drive a bullet down the barrel. With a good lube, it should be no problem to fire 40 or more rounds without cleaning and still load easily.

Well, that should get you on the paper at 100 yards without too much trouble. Now play with load, lubes and bullets to learn the tricks of your particular musket, and have fun!

Your Obd’t Svt,
Tony Beck

Return and Related Links: