Author Topic: 357 MAX: shortest barrel that allows max velocity? (Read 1945 times)

blind ear · « **on:** May 18, 2010, 07:16:13 PM »

Does anyone know the average shortest barrel that will allow the maximum velocity with 180 grain bullets, and any other weights, in the 357 Maximum? I searched several ways but didn't find anything.
eddiegjr

Spanky · « **Reply #1 on:** May 18, 2010, 07:36:57 PM »

Your question doesn't really make sense. A shorter barrel isn't going to give you maximum velocity.
If you are asking how fast you can push a 180gr. bullet out of a 16" barrel or an 18" barrel or whatever... that is a different question altogether.
Did you have any particular barrel length in mind? What loads do you plan on using?
Give us a little more info on what you have in mind and someone can probably help you out.

Spanky

blind ear · « **Reply #2 on:** May 18, 2010, 07:51:29 PM »

The shortest barrel that the 357 max can have and still get average maximum velocity with a 180 grain bullet useing pistol powders. EX: a 22 LR gets average max velocity from about an 18 inch barrel. As the barrel gets longer the returns deminish "or" velocity can drop if the barrel is too long. I want to shorten my barrel but want to get good performance from the 357 Max round with 180 grain bullets. Any Better? eddiegjr

LaOtto222 · « **Reply #3 on:** May 18, 2010, 08:02:50 PM »

I am not sure if anyone knows what length barrel will give you the highest velocity. In other words when does more barrel length give you less velocity. I know that studies have been done on a 17 HMR. They took a barrel that was 24" or 26" and started to chop off an inch at a time and noted the velocity. It was determined that a 18" - 19" barrel gave the highest velocity. Longer than that would yield less velocity and less than 18 would also give you less velocity. For a 357 Max, you would have to start with a 28"- 30" barrel and then do the same thing, starting cutting an inch off at a time until your velocity started to drop off, instead of increase. I do not know for sure, but I would think that the powder you were using would have some influence on what length barrel would give the highest velocity. Just guessing, I would say that some where around 18" would be a good length - not that it would yield the highest velocity, but the velocity gain after 18" would be small. I have a 26" 221 Fireball and a 18" 221 Fireball. There really is not a whole lot of difference in their velocities. The 26" shoots less than 100 fps faster than the 18" barrel. That is not much considering 1 is 8" longer. Good Luck and Good Shooting

trotterlg · « **Reply #4 on:** May 18, 2010, 08:33:30 PM »

My guess would be in the 24 inch range. There is a lot of extra powder in the max case. It may even be longer. Someone with some ballistic calculation programs can probably tell you about some predicted velocity/length simulations. Larry

petemi · « **Reply #5 on:** May 19, 2010, 02:10:15 AM »

I have 16.5 and 22 inch Max Handis. When I get a moment I'm going to chrony them with the same factory ammos in .38, mag and max. and find out if there is any appreciable velocity loss in the shorter barrel. My thought is that factory Max ammo uses powder made to burn completely in a handgun barrel. I know we all gain some velocity in the longer rifle barrel, but at what point does that advantage end? I doubt if I'm going to find much of a difference, and that's why I cut down the shorty.

Pete

Swampman · « **Reply #6 on:** May 19, 2010, 06:51:50 AM »

The cartridge was designed for a 10" barrel.

Blackhawker · « **Reply #7 on:** May 19, 2010, 07:00:33 AM »

Many factors influence muzzle and terminal velocity. Some of them are:

Barrel length
Powder type and charge
Primer type
bullet type (cast, jacketed, gas checked)
Bullet profile (pointed soft point, flat nose, hollow point, etc)

...these are just a few major contributors to velocity. I don't think anyone has a database that includes all of these variables. You have to get out there and test them yourself if you're looking for answers.....sorry to say.

Dweezil · « **Reply #8 on:** May 19, 2010, 07:18:48 AM »

Maybe this will help. Has info on .357 Magnum. Not Maxi.

www.ballisticsbytheinch.com

Blackhawker · « **Reply #9 on:** May 19, 2010, 09:17:58 AM »

Great Link! Imagine the amount of work it took to generate that much data and they never even tested reloads with varying powders, charges, and bullet types.

Thanks for posting that link Dweezil....that's really cool info!

Dweezil · « **Reply #10 on:** May 19, 2010, 12:05:55 PM »

As I recollect, it was actually someones Master's research project at the University of Iowa. Can you imagine doing graduate level work in external ballistics? Kinda cool.

Airsporter · « **Reply #11 on:** May 19, 2010, 12:34:55 PM »

Years ago there was an article in one of the gun magazines (Gun&Ammo maybe?). Anyway, they tested several handgun cartridges in 4" to 8 3/8" barreled handguns v. lever action and semi-auto carbines. By far and away, the .357 mag. was the biggest winner for velocity gains. Most auto cartridges (like 9mm Luger and 45ACP) were designed and loaded to burn very efficiently in relatively short barrels. The .357 and .44 mag really shined in 16"-18" barrels, picking up 500 - 600fps.

zoner · « **Reply #12 on:** May 19, 2010, 01:05:57 PM »

pick a load, chrono it,chop an inch off,chrono it,chop nuther inch,chrono it....you'll get your answer. $:-\$ well, then you need to buy a new barrel

gendoc · « **Reply #13 on:** May 19, 2010, 01:47:46 PM »

Quote from: Dweezil on May 19, 2010, 12:05:55 PM

As I recollect, it was actually someones Master's research project at the University of Iowa. Can you imagine doing graduate level work in external ballistics? Kinda cool.

hmmmmm, sounds familier.......

petemi · « **Reply #14 on:** May 19, 2010, 04:24:09 PM »

[quote The .357 and .44 mag really shined in 16"-18" barrels, picking up 500 - 600fps.
[/quote]

That would lead me to believe that since the .44 Mag and .357 are popular carbine loads, the manufacturers my be loading a compromise load for rifles and handguns.

possibly?

Sometimes, the ideas that surface here wake you in the middle of the night and ya gotta go look into it. Now, there's at least three addictions related to Handis. I've got all three and Dr. Tim is 2000 miles away

Pete

blind ear · « **Reply #15 on:** May 19, 2010, 05:06:32 PM »

I understand what you guy's are saying. I guess I will leave my barrel long and wait until some data shows up. I could shorten and chrony but streaching back out when the velocity begins to drop would be difficult. I wan't to get most of the energy I can out of the MAX barrel (the muzzle blast factor keeps popping up in the back of my mind also). Thanks for your input.
eddiegjr

billy_56081 · « **Reply #16 on:** May 19, 2010, 05:46:27 PM »

I would guess you would have to start with a 40" barrel. Also different burn rates on powder will cause velocities to max out at different barrel lengths.

Blackhawker · « **Reply #17 on:** May 20, 2010, 04:44:42 AM »

Quote from: Dweezil on May 19, 2010, 12:05:55 PM

As I recollect, it was actually someones Master's research project at the University of Iowa. Can you imagine doing graduate level work in external ballistics? Kinda cool.

I work at a college and unfortunately, the mentioning of the word "gun" will probably bring on a swat team.

44 Man · « **Reply #18 on:** May 20, 2010, 07:41:10 AM »

It's a pistol round and that limits powder capacity compared to a rifle round. I would think that 18" would be the best for it. Most pistol rounds gain well up around 14"/16" of barrel and less and less per inch after that. With the extra powder cap of the Max over the Mag, I would guess that an 18" barrel would be just about perfect. Some smaller pistol rounds (45 acp and 9mm) actually gain so little past a 12"/14" barrel, it is silly to shoot them in a rifle barrel any longer than minimum legal length. If I were looking for a 'Handi' length that would still give me good performance, I'd go with an 18" and never look back. 44 Man

GrampaMike · « **Reply #19 on:** May 20, 2010, 08:26:52 AM »

eddiejr

Thanks for the idea. Just put it on my list of things to do. "What is the idea barrel length for 357 Maximum with 180 grain bullet". Of course it will be only a ballistic software test model. What are my 180 grain bullet choices? Mike

blind ear · « **Reply #20 on:** May 20, 2010, 12:53:59 PM »

GrandpaMike

I don't know but for theory and software it would seem that all 180 grain bullets would be the same for initial velocity. Different bullet shapes would make a difference in downgange velocity.

Jacketed bullets would take the pressure. ?

Thanks for the interest.
eddiegjr

GrampaMike · « **Reply #21 on:** May 20, 2010, 01:07:57 PM »

Not all 180 grain bullets are the same length. How much usable volume after the bullet is seated/C.O.L. is what I need to calculate. Granted this is not a big thing... but I am a little crazy about being exact. I will use the Beartooth 180 gr and 185 gr hard cast as 2 of the bullets. I do have a 10", 14", 21" and 22" 357 Max barrels (3 TCs and 1 Handi) that I could use for actual testing. So this info is of interest to me also. Thanks, Mike

GrampaMike · « **Reply #22 on:** May 20, 2010, 03:32:03 PM »

Eddiejr

It turned out to be an easy thing to find out.

Using the Hornady 180 grain HP-XTP bullet.
The powder that produces the highest velocity is Hodgdon LilGun.
With this powder the optimum barrel length is 20.8"

Using the Hornady 200 grain SP bullet.
The powder that produces the highest velocity is Hodgdon LilGun.
With this powder the optimum barrel length is 14.7"

Using the Hornady 200 grain RN bullet.
The powder that produces the highest velocity is Hodgdon LilGun.
With this powder the optimum barrel length is 12.3"

As you can see matching a bullet and powder can change numbers alot. I did not realize this. Maybe this is why some combinations are more accurate in some guns than others. That is so much fun to find THE right combo for each of our guns.

dpe.ahoy · « **Reply #23 on:** May 20, 2010, 04:44:26 PM »

LilGun in the front of the pack again, that powder continues to amaze me. I know it is the best for me in the 357 mag and now the max. I also use it in my heavy 45 Colts and will be loading some 44 mags with it also. Thanks for your testing, GrampaMike. DP

tykempster · « **Reply #24 on:** May 20, 2010, 05:32:39 PM »

For max velocities I'd think you'd need a barrel well into the 24"+ inch area. It may get quite small after 20" or so, but I imagine the gains would be there.

Rustyinfla · « **Reply #25 on:** May 20, 2010, 05:55:43 PM »

I purchased a book in CD form from Paco Kelly @ leverguns.com and the article he does there claims that there is still a velocity gain going from 20-24". How much you gain would depend on the powder used.

GrampaMike · « **Reply #26 on:** May 21, 2010, 05:28:45 AM »

Optimum barrel length here means the "peak" of the acceleration curve. The bullet is still accelerating after this point, but at a slower rate. Actually in the test model the barrel was 40+ inches before the bullet was losing velocity.

LilGun seems to be a great powder for straight-walled cases.

This stuff is really fun.

blind ear · « **Reply #27 on:** May 21, 2010, 06:01:34 AM »

GrandpaMike:

My barrel is 22" so I will get it drilled and tapped for the front sight just like it is. Thanks for the information.

eddiegjr

zoner · « **Reply #28 on:** May 22, 2010, 03:05:34 AM »

years ago i read an article by Wiley Capp pertaining to the 180 gr versus the 158 gr bullet in 357 mag.....the 158 gr bullet start out faster but sheds velocity faster cuz of the 180 gr bullets momentum....at about 50 yds the velocity is the same for both bullets and beyond that the 180 gr bullet is the clear winner.....it's actually going faster than the 158....more momentum,more bullet weight, more penetration. Based on that it seems we should be using the 180 gr bullet to kill game

dpe.ahoy · « **Reply #29 on:** May 22, 2010, 05:37:03 AM »

GrampaMike, Could you give me an idea on the charge weight for the 180gr Hornady and LilGun? I'd like to start working up some loads with that powder. DP