I'll soon be purchasing a S&W 627 snubbie .357 8-shot (with the unfluted cylinder) and replacing the stock boot grips with Hogue target-style grips. Any of you external ballistics/trajectory geeks out there care to offer some estimates on the hold-over that would be needed with this revolver to successfully put plain-jane factory 125-grain .357 mag ammo onto an IPSC-sized target at 200 yards? I'm talking hold-over with classic sight alignment, not tilt-up of the front sight. What would be the hold-over to perform the same feat with 158 grain .38 special ammo?
Long Distance Snubbie Challenge with 627 PC (2 5/8" bbl)
- Thread starter Jeekay29
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tom turner
US Veteran
BAD NEWS . . . Gotta know the Ballistic Coefficient of the specific bullet type design (AND the specific make of that type bullet) of the 125 and 158 gn bullets to know what amount of air drag is put on the bullet in flight.
Also, the velocity of the load you are firing from that length barrel.
GOOD NEWS . . . The bullet is gonna go where its gonna go, so once you get a fairly "close" but accurate expected trajectory it will be enough for your to learn what the sight picture looks like above your intended impact point on that type of target.
Then, from the bench and sandbags, you can begin to shoot enough ammo to make sure exactly what your "rainbow" is.
If you load your own ammo, check your reloading manuals for the information you need. If you shoot factory stuff, contact the factory and see if they'll work up some estimated charts for you through that 2 5/8" tube.
Shooting handguns at 200 yards is FUN . . . once you know your aim point. Technically, your anticipated group will be in a multiple of your normal group at a given distance. For instance, if you can shoot a 2" group at 50 yards, at four times that distance you should theoretically get an 8" group. (If your group size is 8" at 50 yards it would theoretically group inside a 32" circle at 200 yards. Ya just gotta know where the center of that theoretical circle actually is!!!
Then again . . . wind speed and drag on a relatively "slow velocity," bumblebee-shaped bullet can wreak havoc on those group sizes!!!
In any event, it is fun to discover your amount of holdover and then amaze your friends who think you are an amazing shot. Again though . . . the bullet will go exactly where it is gonna go, and if you do YOUR job it will go where YOU want it to go too!!!
Also, the velocity of the load you are firing from that length barrel.
GOOD NEWS . . . The bullet is gonna go where its gonna go, so once you get a fairly "close" but accurate expected trajectory it will be enough for your to learn what the sight picture looks like above your intended impact point on that type of target.
Then, from the bench and sandbags, you can begin to shoot enough ammo to make sure exactly what your "rainbow" is.
If you load your own ammo, check your reloading manuals for the information you need. If you shoot factory stuff, contact the factory and see if they'll work up some estimated charts for you through that 2 5/8" tube.
Shooting handguns at 200 yards is FUN . . . once you know your aim point. Technically, your anticipated group will be in a multiple of your normal group at a given distance. For instance, if you can shoot a 2" group at 50 yards, at four times that distance you should theoretically get an 8" group. (If your group size is 8" at 50 yards it would theoretically group inside a 32" circle at 200 yards. Ya just gotta know where the center of that theoretical circle actually is!!!
Then again . . . wind speed and drag on a relatively "slow velocity," bumblebee-shaped bullet can wreak havoc on those group sizes!!!
In any event, it is fun to discover your amount of holdover and then amaze your friends who think you are an amazing shot. Again though . . . the bullet will go exactly where it is gonna go, and if you do YOUR job it will go where YOU want it to go too!!!
You actually have to know 4 things to calculate a bullets trajectory:
Height of the front sight above the bore axis.
Muzzle velocity of the bullet.
Ballistic coefficient of the bullet.
Distance at which the gun is sighted in.
You can then use a ballistics program to calculate the trajectory. Hornady has a very user-friendly version at their website. Plugging in some reasonable numbers, the holdover at 200 yards for the .357 load would be about 3 feet but for the .38 special load it would be about 8 feet!
The only way to get an accurate muzzle velocity is to measure it in your gun. There can be substantial differences between two examples of a particular model gun with the same load. Your best bet is to try some numbers with the Hornady ballistic calculator and then use these as a starting point with your gun and ammunition. At 200 yards, small differences in muzzle velocity can make a big difference in point of impact.
Height of the front sight above the bore axis.
Muzzle velocity of the bullet.
Ballistic coefficient of the bullet.
Distance at which the gun is sighted in.
You can then use a ballistics program to calculate the trajectory. Hornady has a very user-friendly version at their website. Plugging in some reasonable numbers, the holdover at 200 yards for the .357 load would be about 3 feet but for the .38 special load it would be about 8 feet!
The only way to get an accurate muzzle velocity is to measure it in your gun. There can be substantial differences between two examples of a particular model gun with the same load. Your best bet is to try some numbers with the Hornady ballistic calculator and then use these as a starting point with your gun and ammunition. At 200 yards, small differences in muzzle velocity can make a big difference in point of impact.
Sparrowbird
Member
That 3 feet to 8 feet hold over at 200 yards will be a very small amount when your looking through your sights. The times I have shot at that distance we were shooting across a valley so it was hard to really determine our exact holdover due to the gradually rising ground. Once we got it figured out boy did we have some fun.
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