I just did a little experimenting. I was somewhat impressed with my 4 inch Python but a little disappointed in my 6 inch Highway Patrolman.

.357 Magnum 158 gr. LSWC (Hard) 4 inch 1980 Colt Python

14 grains 2400: 1246, 1234, 1260, 1238, 1176, 1233

14.3 grains 2400: 1220, 1256, 1220, 1263, 1200, 1178

14.4 grains 2400: 1258, 1219, 1219 (nonread?), ERR 2, ERR2, ERR2

14.5 grains 2400:1311, 1341, 1323, 1333, ERR2, ERR2

14.6 grains 2400: 1353, 1345


.357 Magnum 158 gr., LSWC (Hard) 6 inch 1977 Smith & Wesson Highway Patrolman M-28-2

14.3 grains 2400: 1216, 1205, 1238, 1204, 1215, 1243, 1269

15.0 grains 2400: 1356, 1363, 1363


Particularly on the 14.3 grains of 2400, the Python did as well or slightly better than the Highway Patrolman with a much longer barrel.

I'm wondering if I should see a gunsmith about having the gap between cylinder and force cone closed by having the barrel screwed in a tad more. (visually it looks like the Highway Patrolman has wider cylinder gap than the Python.)

With extreme respect, try some other loads. It's that simple. Every single firearm ever made, will produce different velocities with various loads. That's just the way it is. Longer barrels do not always produce the highest velocities... shorter barrels do not always out perform snub noses... depending on the load used. This is true of all long arms and handguns, including run of the mill guns like Colt... and even truly remarkable guns like S&W. :-). In all seriousness, bc gap is only one of a number of factors in what velocity a revolver produces with a particular load. JMHO. Sincerely. brucev.

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Here's a link to an article, originally published in one of the earlier Speer Reloading Manuals. It really sets to light the variances in components, guns, etc.:

Why Ballisticians Get Gray

I pains me to retell the story but you struck a chord with me. Same experience, different page. I bought a beautiful 4"Python that had been custom shopped by Colt for a local Lawman. I loved shooting it as it would shoot anything put into it accurately. I got the itch for a 6" Python about 15 years later and couldn't afford the then Python prices. I wasn't gunsmithing at the time so had a local Pistolsmith swap the barrels. He reduced his price considerably by him keeping my 4" barrel. I didn't get to shoot the new 6" Python for about 6 months. It shot patterns NOT groups. I worked for a year trying to find something it would shoot. Even the velocities were all down from the original 4" bbl. I finally gave it up and sold it. The Pistolsmith was long gone and couldn't get my original barrel back. I learned a big lesson. ........... Big Cholla

They used the same make, model, and barrel length of many guns and got widely varying results.

Tighten up the gap only if is out of spec. The difference may be in the exact size of the bore.

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"He was kinda funny lookin'"

Real world ballistics don't always follow the "rules" like "longer barrel = more velocity." Personally, I'd say "don't sweat it." Nothing you ever shoot is going to know the difference. Strive for consistency and accuracy and don't spend too much time worrying about a few fps one way or the other. JMO, of course.

You are expecting too much! While, as a general rule, longer barrels will give higher velocities than shorter barrels 'taint always so!

Example from some of my own guns:

.38 Spl. My 5" M&P Built ca. 1950 delivers higher velocities than my 6 1/2" Outdoorsman. It does this consistently.

.38 Spl. My 1927 Colt "Officers Model Target", which is a 7 1/2" gun, is consistently slower than most of my 4" and 5" S&W revolvers, with the same load.

.357 Magnum. My 4" Model 19 consistently delivers velocities equal to my 6" HP or 6 1/2" Model 27.

Mixed: The 4" 19 gives higher velocities with .38 Spl. than the above 5" M&P, even though the M&P is "faster" that the longer guns!

Handguns, revolvers in particular, are dynamic mechanisms which contain un-quantifiable dufferences in construction which defy identifying why one gun is "faster, or slower" than another when everything appears to be identical. I have set barrels back in revolvers to reduce the barrel-cylinder gap because "everyone knows" that this affects velocity! Even reducing the B-C gap from .012 t0 .004 in one case, resulted in absolutely zero average velocity change when chronographed with the same loads both before and after the adjustment! Go Figure!

Each gun is a law unto itself and will give whatever performance it will. No, it isn't logical, but it is just the way things are in revolver performance.

Python's are wonderful revolvers and I had coveted one for years, but they are not magic.

Yes, I am well aware of these variables. I've even heard tell of snubbies outrunning 6 inch barrels.

At the risk of offending S&W fans, I have heard that Colt barrels tended to produce slightly better velocities compared to some of the S&W counterparts. And a Python has earned the name of "Rolls Royce of Revolvers" (and the Highway Patrolman is officially a "budget gun" although I think this has more to do with irrelevant touchups compared to the M27)

But still, Python aside, I was expecting a little more out of the S&W 6 inch. On average, more or less, most ballistics I've read of tend to have 100 ft per second difference every 2 inches you take or add to the barrel length. (I know it's not written in stone)

I was expecting to at least be well over 1300 ft per second with the 6 inch barrel. So I thought closing the gap between cylinder and cone might optimize the gun

THAT GAVE ME A CHUCKLE, brucev. I AGREE WITH YOU IN THEORY, ALTHOUGH THE FACT THAT THE PYTHONS WERE HAND FITTED MIGHT HAVE SOMETHING TO DO WITH IT. I WOULD ALSO TRY THE SAME LOADS OUT OF A DIFFERENT S&W OF THE SAME MODEL AND BARREL LENGTH IF POSSIBLE……...

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'Nam 1968-69.DAV,VFW,NRA Inst.

Two of my best shooting guns are a 6" Python and a 6" Highway Patrolman.

What they said.

I have experienced similar results a number of times with different guns/calibers. Higher velocity from shorter barrel with exact same load. More often than not I have traced it back to smaller throat diameter. That being said, like others have stated the variables involved give us a myriad of possibilities. One of the things that make handloading so much fun.

My pythons give higher velocities than my model 19 in the six inch versions. Luck? Maybe, maybe not.

Might also be tighter bore on the Python. I had. 2 3/4" ruger ss that was faster than 3 other 4" guns.

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NRA Cert. Inst. IDPA CSO

Is this about velocity or accuracy?

As has been previously noted some barrels just shoot faster than others. As for why, that will likely be a Mystery until NASA or same level scientific organization decides to find out. I can also tell you as a Dan Wesson owner that changes in the Barrel/Cylinder gap don't produce observable differences in velocity until the gap is less than 0.002 inch or larger than about 0.012 inch. So don't waste your money on having that B/C gap tuned unless it's outside of that range.

Yep, I have to agree with scooter on this. I have 2 different Model 27s, a 5" barrel and a 6 1/2" barrel. Both are "new old stock" type pistols I bought recently. The 5" was still virgin; the first rounds it's ever had shot through it besides the proof test rounds S&W shot before leaving the factory were shot over the chrono when I checked this and the 6 1/2" gun had only had 270 rounds or so shot through it by myself from it being virgin, so wear wasn't any factor. And the 5" barrel pistol always shot the same loads faster than the 6 1/2" gun.

The TLDR version of this post is don't sweat it. That's normal gun-to-gun variation.

Using your 14.3 2400 loading results, the average velocity of the Model 28 is slightly higher; 1229.17 as opposed to 1222.83 from the Colt. I ask: is that difference really enough to agonize about?

The Python has a tapered bore smaller toward the muzzle. It can give better velocities from cast bullets.

Try some different powders. I have noticed over the years that 2400, 296/H110, AA#9 and IMR4227 can vary a bit as to the winner with top loads. In one M686 4 inch, the AA#9 load gave a full 100 fps faster than the others with a 187gr WFNGC cast bullet.

Your velocities with the M28 look just fine to me.

As in most things, results do vary!

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Stay safe people!

I had a chance to talk to J.D. Jones about this phenomenon , He said he had NEVER seen an 8 3/8 model 29 produce more velocity with a given load than a 6 in one. He also remarked that he had on occasion seen 4s out perform either. J.D. has as much experience in this as anybody still alive. We have proved here on my range that out of a Ransom Rest you get the same groups from 2 inch guns as you do from 8 3/8, another thing easily proved. The bullet "don't know" how long the barl is.

I have 5 diff 4" 357, all give diff vel. Some are closer than others but one is a full 120-130fps slower with all loads. That is my Smolt with Python bbl, slower than my 4" Python, go figure.

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NRA Cert. Inst. IDPA CSO

There is no need to :shout". Really.

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Not in Kansas anymore, Toto.

I fail to see the problem.

Am I missing something?

I've never been able to document a major difference in accuracy between the two guns. In all fairness I love my Python and have always thought the N frame S&Ws were a bit bulky and heavy for 36 calibre. I prefer the K/L frames for the calibre.

Hey Joe, is your caps lock broken?

Perp hit by .357: "Man, that barely hit 1200 fps, PAW HAW HAW!"

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"He was kinda funny lookin'"

A lot of the loads in reloading manuals are optimized with a particular length barrel. As such, barrels very much longer will actually cause some degradation in muzzle velocity. If the powder has a complete burn in a shorter barrel, say 4", then barrels longer than that will not accelerate the projectile; the longer barrel will cause friction and actually slow down the bullet.

There are also instances where the velocity is determined with a gun having a closed breech. That also changes the results.

Not really. Most modern gun experts didn't know the old timers that really knew a lot about handloading. They did know Elmer Keith, or about him, who's main passion was developing hot loads and cartridges for hunting at long ranges. So that's all they know to write about...Velocity. That's all that matters.

Dennis, this may be true with some calibers using the extremely fast handgun powders but in the case of the 357 Magnum this is NOT true.

I have two 357 Magnum revolvers, a 4 inch 620 and a 6 inch Dan Wesson 15-2. I also have two 357 magnum rifles with 20 inch barrels, a Rossi M92 and an original Winchester 1892 re-barreled in 357 Magnum.

I have chronographed many different loads with both handguns and both rifles and one consistently predictable result is that every single load has produced MORE velocitiy from the Rifles than the Handguns. Powders used range from Accurate #5, 7, & 9, Vihtavouri 3N37, to 4227 and H110/W296.

Now, I will grant that the faster powders don't produce as much of a velocity gain as the slower powders but every single one of these powders does shoot a minimum of 200 fps faster from the rifles. At a guess I would say the velocity peak for Accurate #5 would probably be with a barrel in the 14-16 inch range but that is nothing more than a guess.

The difference between a Highway Patrolman and a model 27 is less finish and lack of some checkering on the top strap to save $$$. Entirely cosmetic. I'd buy one in a minute, but hey, if the Colts generally do better in the velocity department, so be it. On my budget I might be able to afford a mod 28.

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"He was kinda funny lookin'"

Some additional Python 4 inch readings I did this afternoon:

158 gr, LSWC (Hard)

14.3 grains 2400: 1220, 1256, 1220, 1263, 1200, 1178

14.4 grains 2400: 1258, 1219, 1219 (nonread?), ERR 2, ERR2,

14.5 grains 2400:1311, 1341, 1323, 1333, ERR2, ERR2

14.6 grains 2400: 1353, 1345

180 gr SJHP Remington
.357 Magnum 180 gr. SJHP 4 inch 1980 Colt Python 4 inch

1129, 1131, 1125, 1123, 1123

scooter has hit the nail squarely on the head with his post above. With the 357 Mag, you will see a velocity increase with the longer barrel, all else being equal. I actually plan to do some chrono work on 357 Mag with my Coonan Classic and my Rossi 92SRC. Both are non-vented platforms, so any increase in velocity (or lack of) should be directly comparable since neither weapon has a cylinder gap. And I'm thinking of doing the same thing for 9 MM since I have an Uzi with 16" barrel and a Beretta. I think the 357 will show a sizable velocity increase with the slower powders such as Accurate #9 and 296. For 9 MM, I don't think there will be as much difference, if any to speak of.

Considering the massive price difference between a Python vs. a Model 28, I would hope the Python is better at something...

Jim

Most of the work I've seen on the gains from a standard 4 inch combat barrel to an 18 inch rifle barrel is, almost invariably, around a 2:1 power difference. I should buy a chrono myself, but from my shooting of magnum rounds out my Winchester 94ae, all I can say is the difference is night and day. The same 158 grain jacketed semi wadcutters, American Eagle, that I've shot as a budget round, would cut nice holes out of concrete blocks out of my 6 1/2 inch Rossi, and the rifle would turn them into an impressive pile of broken concrete and dust. Every animal I've killed with my Rossi would drop in its tracks, but every small game animal I shot with the rifle almost blew up, skinning squirrels, blowing up racoons, doing high power rifle grade damage. Even without a chronograph, I can tell there is a world of difference in that sealed chamber, and with the longer barrel.

With all the talk about powders, what about bullets? The OP noted hard cast bullets, which will perform better from a naturally tighter barrel, but will perform much worse in a slightly looser barrel. Its been noted that too hard a cast can lead to the bullet not expanding into grooves correctly, with resulting gas leakage, and subsequent loss of pressure. Indeed, it has been noted that harder bullets do not always lead to less leading, but instead sometimes more, via the poor seal's escaping gas burning off lead from the sides into the barrel.

Perhaps if the shooter were to do the same exact loads, but with many castings of the same exact bullet of different hardness, the results could easily flip around, and could be very informative, and surprising. Perhaps a softer bullet would seal better in the 28 and outdo the Colt, perhaps not. But it is a very important factor.

This thread has made excellent points that every gun is different on a small level, enough to throw off the idea of universally equal results from the same barrel lengths of firearm models. In order to figure out the "perfect" load for your individual revolver, one must not only experiment with various loads, but if one casts, the perfect hardness and lubrication to fit the exact nature of that particular firearm.

Your experience proves a few things:

• If you're getting consistent 200FPS increases in using the same load for both guns, then it proves that those loads in revolvers are very inefficient. The revolver loads are leaking gas through the barrel/cylinder gap (normal), and that the rifles are benefiting from a "sealed" chamber (again, normal).
• Ergo, any comparison between a rifle and a revolver amounts to the "apples/oranges" analogy.
• Revolver loads are necessarily inefficient because larger doses of slower burning powders are needed to generate desired velocities.

My point was to note that any load, in any gun, achieves an optimum velocity using a particular type of powder/bullet/primer combination. Once that powder burn has been completed, no further velocity is possible and the projectile starts to slow from friction with the barrel. That's pure mechanical physics. Granted, it's in the field of the hypothetical to a point, and may not affect your results in your tests.

Doug,

Be careful about pushing the pythons to hard. They go from fine to sticky extraction quickly in the range you are in. 14.2 grns is my limit on my Pythons after I wised up a few years back. Keep the 14.5 grns and up in the N frames or the Redhawks with 158's.

No need to stress a fine revolver with more than it likes.

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SWCA 1646

Count me as another to have had a 4in run slightly faster than a 6in .

There are expected rules of thumb , but within any bbl length expect a potential +/- 50fps for cumulative variables in chamber , throat , forcing cone , and bore. Sometimes it will be +50 on the 4in and -50 on the 6in , and they meet in the middle. Theoretically someone somewhere will have a slow 4in and a fast 6in and see a 200fps difference. As noted B/9 gap is only one factor , and may not be the particularily limiting one. My "slow" 6in above was a DW , and closing the gap to .003 made no noticable increase.

For the OP , if both guns give good accuraccy , and vels within the useful range , don't sweat it.

I remember us discussing this over on the Colt forum.

Once in a blue moon I'll have a cartridge feel a little sticky (meaning a spent case won't just fall out, it will need a tad of force before it "pops" out). But most of the time it's fine.

I decided the other day not to go above 14.5 with the Python as I had reached my desired velocity (1300+). But I sure don't want to beat up a fine gun such as that. I would die if I damaged the Python.

He beat me to it.

And IF you can add 40 or 50 fps to the M-28, what will that do for you? I doubt any paper target will know the difference? NO game animal will tell a difference either.

I always shot 15 grs. of 2400, 158 gr. bullet, 1400+fps. I gave it to my son and that is the load he shoots. Larry

Doug, I would suggest doing way more testing than 3 or 4 bullets. That's not a really accurate way to measure velocity, especially with your chronograph having read malfunctions.

Me too. And I plan to. My original plan was to shoot all 6 cylinders.

I'd want to shoot even more than that.

However, you spend time carefully loading 12 upstairs, load half in one gun, half in the other and then your left with 3 or 4 in one gun plus error messages...you don't always have the time to go load up 12 more and try for a more ideal session.

Or, it could just be what my first boss in the machine shop called it, "the perversity of machinery."