I shoot a 4" 629 and I'm asking for information
about reloads that won't cause me to lose muzzel velocity compared to a 6" or 7" barrel.

Using the same optimum powder, in various standard length barrel revolvers, the longer barrel will always give the higher velocity.

Slow powders will always give the higher velocity for a given barrel length.

The shorter barrel loses to the longer one.

You just need to tailor the load to do what you want the best it can in your barrel length.

.

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Waiting for the break of day

4" bbl's are kind of unique in the 44mag. Owned this 4" 29 for a long time & as you can see from the turn lines, it was no safe queen.


Sold it last year for stupid $$$

That being said you have to choose your powder & bullets carefully. Some magnum powders perform better in then others in the shorter bbl's. I tend to use 2400 or faster burning powders in any revolver with a 4" or less bbl length.

A cast bullet will typically have more velocity than their jacketed counterparts. Some running +/- 100fps faster which is huge.

Typically, you step down in weight to increase velocities. Elmer keith did this with his famous swc design. He used a hollow based version of his swc bullet to get more velocity out of this revolver loads for flatter shooting shots at longer distances.

Same end result as what you're trying to do. You want to maintain the velocity of the longer bbl's??? Choose your bullets/powders carefully along with using a lighter bullet.

I used these lighter bullets in that 4" bbl'd 29 along with a 2 1/2" bll'd charter arms bulldog (44spl).


The top left bullet is that 429422 hollow based swc keith liked to use. I simply added a hp to it. The bottom left bullet is what you should be testing. It's a H&G #124, the H&G version of the lyman 429215 bullet.

The H&G #142 (220gr swc/200gr swc hp)/lyman 429215 (215gr swc) are a thompson design. Lyman made 2 versions of that bullet for the 44mag, a 255gr and a 215gr bullet.

It's not that hard to get +/- 1400fps out of a 4" bbl'd 29/629 with the light weight thompson bullet.

Just something to think about.

^^^^^^^^^^^^^^^^
What Forrest r said.

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VCDL, GOA, NRA

There is no "Magic Powder " that will cause a 4" barreled gun to equal or surpass the velocity of a 6" or 7" barrel .
For top velocities in 44 magnum , regardless of barrel length , W296 , H110 and good old 2400 are still your best bets .
Load Safe,
Gary

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Certified Cajun
NRA Member

What gwpercle said. There is no magic potion.

Due to case volume, I believe the burned gases will always increase the velocity in a 6" bbl. This would assume that barrel-cylinder gaps were equal on both guns.

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Front sight and squeeze

If you're talking about the typical 44 medium loads that folks are enamored with (7-8gr of Unique), you can simply up the charge weight a couple grains.
If you're trying to bend the laws of physics to make an interesting thread, well good luck to ya.

Not sure why you want to do that, but if you want a higher MV from a 4" barrel, you should get a chronograph. Start with a known safe load, and increase the powder charge little by little until you get the MV you need.

You should be aware that different revolvers, even with the same barrel lengths and using the same loads, will seldom produce the same average MV. This is primarily because of slight differences in the barrel-cylinder gap width and other dimensions. And for the most part, MV figures given in reloading manuals mean very little.

You might try Longshot - Hogdon recommends 11.0-12.0 grains with a 240 grain bullet for 1249 fps to 1331 fps, 8 3/8" bbl. I used 9.5 for mid-range loads with the Speer 240 lead. Longshot is slower than Unique, faster than 2400. | Hodgdon

Longer barrels usually give more velocity.
Slower powders at the same pressures usually give more velocity.
The laws of physics are still in force.
The recoil and muzzle blast from a 4" S&W will dictate what you will be happy with. JMHO-YMMV

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dd884
JMHO-YMMV

Anything shorter will reduce velocity, that's just how it works! Don't get stupid and cause yourself an issue. Forrestr has is right!

I totally agree with most of what's being said in this thread. Choosing your powder and bullets is the answer. Unfortunately you didn't tell us what load you are building for the 6" barrel and the velocity it generates.

I would say using 2400 or AA#9 will be better than the slightly slower W296/H110 or 300 MP. They will probably deliver a fuller burn in that shorter barrel.

Why are you worried about the velocity drop?
What velocity are you trying to achieve?

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Freedom is never free!!
SWCA #3437

A 250 gr Keith bullet with a max load of IMR4227 will give about 1200 fps in a 4 inch M29. This will give you about all the penetration you will ever need.