The Myth of Needing a Wider Barrel/Cylinder Gap to Shoot Black Powder

[Driftwood Johnson]

Howdy

From time to time it will be stated on this page, or other pages similar to this, that a wider barrel/cylinder gap than normal is needed when shooting Black Powder to help prevent the cylinder from binding.

I have routinely maintained that this is not true. As evidence I usually state that I regularly shoot Black Powder through a variety of guns, Colts, Rugers, and replica colts, and every single one of them has its original, untouched factory barrel/cylinder gap. They all measure between .005 and .008. I also have moderated this statement by saying that if the gap is really tight, down around .002 or so, it may need to be opened up a bit, but that is the only case when a barrel/cylinder gap needs to be opened up, and even then, .005 - .008 is plenty. The trick, of course, is to use a bullet liberally coated with plenty of Black Powder compatible bullet lube, and the gun should have a good sized cylinder bushing to deflect fouling blasted from the barrel/cylinder gap away from the cylinder pin. Revolvers that are particularly lacking in a good sized bushing are the S&W Top Break reproductions made by Uberti, and the 1858 Remington New Model Army.


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I have always liked the appearance of the Bisley Colt. I'm not talking about Ruger's version of the Bisley, I am talking about the original Colt Bisley. The first Bisley I ever saw was an Uberti replica, and ever since then I have liked the unusual look of the Bisley. I decided that if I ever got the chance, I would love to own one.

Recently I became the proud owner of an original Bisley Colt, made in 1908 and chambered for 44 Special. The barrel and cylinder are not original, the original barrel would have said Bisley Model on it. I am pretty sure this barrel is a 2nd Gen barrel, judging by the way it is marked. The cylinder appears to me to be a 1st Gen cylinder, but I am pretty sure it is not original either since Colt did not chamber the SAA for 44 Special until 1913, and Kuhnhausen says no Bisleys ever left the factory chambered for 44 Special.

None of that really means too much, I was told when I bought the gun that the cylinder and barrel were not original. Nobody was trying to pull the wool over my eyes. I may letter the gun at some point to find out more about it.









But what does all this have to do with tight B/C gaps and Black Powder you ask? Well, it turns out this gun has a very tight Barrel/Cylinder gap. Only around .003. When I bought it, I intended to shoot it in CAS, and of course I intended to shoot it with Black Powder. I already load 44 Russian with Black Powder, and that is what I expected to shoot in the Bisley for CAS.

The first trip to the range was just a shake down cruise with Smokeless 44 Special loads. It performed like a champ, hitting pretty much at point of aim at standard CAS pistol distances.

Next, I took it completely apart, doused all the parts in lacquer thinner to completely remove all oils, then reassembled it, liberally lubing it with Ballistol. This is pretty much my standard procedure for any revolver that I intend to mainly shoot with Black Powder.

My 44 Russian loads have 1.3CC (about 20 grains) of Schuetzen FFg under a 200 grain Mav-Dutchman Big Lube bullet sized to .428 and lubed with SPG. Seating the bullets and crimping them at the crimp groove compresses the powder just a tad under 1/8". I slugged the bore of the revolver, and it came out right at .428. The .428 bullets were also a good fit in the chamber mouths, they just need a little bit of a poke to push them through. My only fear was that with that .003 B/C gap, I might need to open it up a bit.

I grabbed 100 of my BP 44 Russian rounds and headed back to the range. After about 50 rounds the cylinder did start to bind a little bit. Not enough to really be a problem though. By the end of the 100 rounds the gun was complaining a bit, but it was still shooting and cocking the hammer still rotated the cylinder, although it was getting a bit sticky.

I was very happy. Clearly, 100 rounds is much more than I will be putting through it at any CAS match. At any regular six stage match I will probably only be putting 30 rounds through it. Even at an eight stage match, 40 rounds should be no problem, and if it does start to bind a bit, I can always pull the cylinder and wipe it down a bit. Recoil with just 20 grains of FFg is very mild. I may load up some 44 Specials with a little bit more powder in them, or I may just shoot the old girl with those light Russian loads.

 

[hang fire]

Broad statement that tight B/C gap and using BP has no effect on binding up revolvers. I have found the reverse, but congratulations on yours.

 

[Carl N. Brown]

I have a couple of old brass frame cap'n'ball that have over the decades developed wide barrel/cylinder gap. I don't really recall binding problems when they were tight, but I do know with the wider gap, I have had to return to BP from substitutes because the wider gap does not allow substitute powders (Pyrodex, etc) to burn well.

 

[Driftwood Johnson]

Perhaps I should have been more specific.

On the various shooting boards I frequently hear it stated that to shoot a cartridge revolver with Black Powder the barrel/cylinder gap needs to be opened up to about .012.

I shoot a lot of Black Powder. I shoot it in Colts, Rugers, and Colt clones. None of these revolvers has had their barrel/cylinder gaps opened up. They are all in the range of .005-.008. They all shoot Black Powder very well.

I used to pan lube regular hardcast Smokeless bullets with a 50/50 mixture of Crisco/Beeswax. Using this mixture with conventional bullets with rather thin lube grooves, cylinders could bind. And with pan lubed hard cast bullets my rifles started to get an accumulation of hard fouling near the muzzle after 20 or 30 shots. However for the last several years I have been casting my own Big Lube bullets. These have one huge lube groove. I size and lube with SPG. The huge lube groove provides enough lube to keep the fouling in the bore of a rifle moist for its entire length, so there is no build up of hard fouling. And these same bullets keep any fouling blasted out of the barrel/cylinder gap moist too, so it does not build up on the cylinder face and start to cause binding. It gets wiped off as the cylinder turns. In addition, soft, moist fouling blasted out of the barrel/cylinder gap will tend to bind up a revolver less at the cylinder pin, which is where most of the binding occurs. Hence my earlier comments about cylinder bushings.

As I stated, I was afraid I might have to open up the gap on my Bisley Colt to around .005 -.008, but using Big Lube bullets with plenty of SPG lube on them, it performed fine and does not need the gap opened.

As I stated earlier, the S&W Top Break replicas that Uberti makes, and the Remington 1858 New Model Army, do cause binding problems, not because of a lack of soft lube on the bullets, but because of the small cylinder bushing Uberti supplies with their Top Break replicas, and the total lack of a bushing on the face of the 1858 Remington cylinder.

 

[Legionnaire]

I have not shot enough black powder through enough different revolvers to have an informed opinion on the question of cylinder gap. But I do know a sharp looking revolver when I see one, and that is definitely one! Thanks for posting the pics!

 

[Greg528iT]

Ditto, great looking revolver. Good information. Thanks for sharing.

 

[arcticap]

Oyeboten and others have often told us about how effective using paper thin wads or discs impregnated with lube are. Here's one of his posts about it, and his lubrication methods are mentioned throughout the entire thread about testing BP cartridges in 2 revolvers. Some bullets aren't designed to hold much lube but his paper wafers seem to work well as an alternative.

Lubed paper towel wafers:

http://www.thehighroad.org/showpost.php?p=6011096&postcount=19

Thread:

Range Report: Black Powder .38 S & W 'Special'

http://www.thehighroad.org/showthread.php?t=483583&highlight=towel

 

[Driftwood Johnson]

Oyeboten and others have often told us about how effective using paper thin wads or discs impregnated with lube are. Here's one of his posts about it, and his lubrication methods are mentioned throughout the entire thread about testing BP cartridges in 2 revolvers. Some bullets aren't designed to hold much lube but his paper wafers seem to work well as an alternative.

I was doing the whole lube cookie and lube wad thing for a while back when I was pan lubing my bullets for Black Powder. Yes, it does work, but it adds a whole nother step to the loading process. That's why I only use the Big Lube bullets with Black Powder these days. Just seat the bullet and crimp it, no extra steps like lube cookies or lube wads. When you shoot as much Black Powder as I do in CAS, around 20 pounds per year, it makes sense to streamline the process.

I'm really far behind with my Cowboy loading this year, got lazy over the winter and didn't load up anything. Just loaded up six boxes of 44 Russians on Sunday, still have to load up a whole bunch of 45 Colt, 45 Schofield, 44-40 and 12 Gauge. When you load that much of that many cartridges, streamlining the process as much as possible, by leaving out wads and stuff, really makes a difference.

In case anybody is not familiar with the Big Lube bullets, here is a photo of the components I use for my 44 Russian rounds. The bullet at the right is a 44 caliber Mav-Dutchman Big Lube 200 grain bullet. On the left is one sized to .428 and lubed with SPG. The powder charge is 1.3CC (approx 20 grains) of Schuetzen FFg. At the rear are an empty Starline 44 Russian case, and a completed round.



This photo illustrates why no extra lube is needed with these bullets, they carry more lube than just about any other bullet in existence.

 

[BHP FAN]

I LIKE those grips. mis-matched or not, that pistola is a rare beauty.

 

[andrewstorm]

when my R O A binded......

After a hole day of shooting triple seven.....it wasnt no myth,it was a very tight old army,new in fact,and 30 grain loads under buffalo ballets,with cci caps,bound it up tight,hammer and cylinder gap

 

[Driftwood Johnson]

After a hole day of shooting triple seven.....it wasnt no myth,it was a very tight old army,new in fact,and 30 grain loads under buffalo ballets,with cci caps,bound it up tight,hammer and cylinder gap

Sometimes I don't know why I bother to post on this board.

I was speaking about real Black Powder and Big Lube bullets, that carry enough lube to keep the fouling from getting hard.

 

[Jim K]

It is interesting that almost all discussion in regard to the b/c gap involves too large a gap and the effects of fouling if the gap is too small.

But too tight a gap, in any revolver, can be a problem for another reason - heat. When a revolver is fired with some degree of rapidity, the cylinder expands lengthwise enough to bind if the gap is too small (.004" or less). I have seen several threads on the binding problem, and in every one, the cleanliness gurus insist that the problem is fouling and that all will be well if the cylinder is properly cleaned with a wire wheel, belt sander, floor polisher, 20 grit sandpaper, or whatever the "cleanliness" experts are advising this week.

The real problem for a small b/c gap is heat, not the kind of powder used. So the shooter has either to resign himself to letting the gun cool after each cylinder or increase the b/c gap to something more reasonable, in the .005"-.008" range.

Jim

 

[junkman_01]

Sometimes I don't know why I bother to post on this board.

I agree with that statement!