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View Full Version : So.. ammo faster in pistol or rifle???


Dragon55
February 21, 2010, 09:37 AM
OK.. so I'm gonna go out today and play with my chrony some more.

So... folks with lots of experience with a chrony, make your predictions.

I'll be shooting some fairly cheap .22 ammo in a Remington model 522 VIPER rifle and a Browning Buckmark with a fairly heavy barrel that is 5 1/2" long. (I have no idea what specific model it is since it doesn't state on pistol anywhere.

The ammo will be:
--Winchester Super X HP's 37 grains states on box 1330 fps
--Winchester Wildcat LRN 40 grains states on box 'high velocity'

I have read on this forum numerous times that the same ammo will always go faster out of a rifle than a pistol. Since I want to see for myself I thought I would test.

So.... what are your predictions????

Dragon55
February 21, 2010, 10:52 AM
Well that didn't take long.

Super X range from both guns 1120-- 1337

Wildcats range from both guns 992 -- 1183

I shot 10 shot strings from each gun.

4thPointofContact
February 21, 2010, 03:02 PM
So, pretty much same velocity in either?

Dragon55
February 21, 2010, 06:11 PM
No very different. I am just surprised none of the armchair experts on here wanted to guess.

I think many just want to tell you why it is instead of predicting what it will be.

Brian Pfleuger
February 21, 2010, 10:28 PM
I don't know that I've heard that "ammo will always be faster in a rifle". Certainly it is generally so. Equally certain, it is not always so. Some ammo is optimized for certain barrel length, either by design or coincidence, and will lose speed in barrels longer than that length. Usually the length that speed begins to drop off will be somewhere greater than about 15 inches with handgun ammo but I wouldn't be surprised if a rather low pressure round like the 22 will stop gaining speed well short of that length.

Dragon55
February 23, 2010, 08:27 PM
Sorry no... 16% faster in rifle

4thPointofContact
February 23, 2010, 08:37 PM
Thanks. Wasn't sure from the listing of lowest and highest velocities what the average of each was.

Brian Pfleuger
February 24, 2010, 11:55 AM
16% faster in rifle

The rifle has a 20 inch barrel, correct?

That's only a 16% gain with a barrel of more than 3 1/2 times the length. I'd be willing to bet that there is a length somewhere in between that would match or exceed the velocity produced by the rifle. My guess is right around 15 inches.

Scorch
February 24, 2010, 01:36 PM
Just FYI, Jim Carmichael did a test on this back in the 1970s sometime. IIRC, he came up with 16" being the ideal for velocity but standard deviation was high; 19" gave the most consistent velocity; and after 21" of barrel length there was a net velocity loss. Pressure measurements showed that a 22LR cartridge developed maximum pressure before the bullet had completely exited the case, and pressure dropped consistently after 2" of travel. Your tests show a very similar scenario, with a 5" handgun giving 80% of the velocity possible from a rifle barrel.

Years ago, 22LR rifles were common with 24"-26" barrels, but longer barrels give a longer sight radius which contributes to shooter accuracy. With optical sights being the norm nowadays, there is no reason why you should not have a shorter than 20" barrel.