Pistol Caliber Carbine Zero(ing)
Posted by Strong_Dentist_7561@reddit | Firearms | View on Reddit | 15 comments
I’m looking at a .357 Magnum carbine for sub 100yd hunting, close range pest control, and serious social work… in my perusing of the interwebs; I’ve stumbled upon several sites indicating that POA/POI can and will change drastically based on different cartridge loadings compared to a genuine rifle cartridge.
How true is this, especially in regards with iron sights- is it genuinely an issue to be taken into consideration and needs a new zero for each load, something that can be remedied with holdover/under, or internet Fuddlore that’s been blown entirely out of proportion ?
Stock_Block2130@reddit
Are you aware of the gundata.org ballistics charts and graphs? They show the rise/drop for many cartridges and bullets. You can heavily customize the inputs for muzzle velocity, sight or scope height, etc. There are other charts on the internet that show the relationship between muzzle velocity and barrel length for many standard pistol rounds.
Future-Beach-5594@reddit
Havnt seen a 357 pcc in Person yet but i would imagine it would be fun. I mean my 9mm is like shooting a paintball gun and does indeed do it out to 100 yards pretty accuratly.
Kevthebassman@reddit
Yes, absolutely. Hell, my Rossi 92 has a wandering zero depending on how hot it gets. It’ll string vertically by 6” at 100 yards over the course of 20-30 rounds.
At any rate, lever actions are ill suited to “serious social work.”
They never caught on for that because they are easy to jam up in a panic, and the jams are not easily cleared.
Get a bolt action if you need a non-semi auto for serious social work.
Strong_Dentist_7561@reddit (OP)
Never mentioned a lever gat… Ruger makes a 77/357, and aftermarket 10rd mags
Kevthebassman@reddit
You’re on the right track then. You will have to excuse my assuming you were speaking of a lever actions, as you are no doubt aware there is a huge trend of taking sleek, handy carbines and hanging two pounds of rails and other shit off of them to try and make them something they’re not.
Diligent-Parfait-236@reddit
Because most rifle cartridges are loaded to cycle an automatic action, there is a significantly smaller window of common loadings, POI changes can still be highly relevant in hitting the target, but nothing on the order of magnitude of a cartridge primarily loaded for non-automatics.
DBDude@reddit
It matters in general for any rifle. But most loads have fast burning powder, of various speeds, to keep high pressure behind the bullet in a short barrel. Now you have a long barrel that can use consistent pressure for the duration. Find one meant for rifles, or load your own using a rifle-friendly (slower burning) powder. Lil Gun seems to be popular.
Also whether your cartridge is loaded with regular or magnum primers have an effect. Magnums give a touch more oomph.
iBoofWholeZipsNoLube@reddit
Depends on what you wanna do with it. For silent stuff you will be exclusively using 148gr wadcutters. Once you hear it you will not care about any other zero. For deer and man you want 158gr+p hollow points so that's a zero you ought to know. For cheap(er) plinking you gotta know where 130gr .38 hits. From a 2" snub nose revolver, 130gr will generally pattern anywhere from a quarter inch to a full inch and a quarter lower than 158gr at 25 yards. I'd assume it's much less from a rifle and at 100 yards, the holdover is not gonna be more than a 5" difference. 8" targets are a nickel so it's just a range trip to figure it out.
Strong_Dentist_7561@reddit (OP)
Any reason one couldn’t zero XYZ 158grn load at 100yds, then figure hold for everything else ?
iBoofWholeZipsNoLube@reddit
Nah that should work
DarthMonkey212313@reddit
Assuming mag or tube fed on a bolt or lever carbine here(no energy loss to action cycling or cylinder gap). By sticking to a carbine which should have a 16 or 16.5" barrel, and avoiding the super light 110gr and lighter stuff, you can avoid the situation where the bullet actually starts slowing in the barrel. You'll still have POI shift between loads, but it shouldn't be too bad.
Ornery_Secretary_850@reddit
Even "genuine rifle cartridges" have greatly different POA/POI depending on the load being used.
As an example. .300 Weatherby 110 gr vs .300 Weatherby 220 gr.
ServoIIV@reddit
At 100 yards or less most of the difference will be due to differences in the muzzle velocity. A 357 magnum carbine can use a wide variety of loads from 38 special loads that are subsonic to some very hot full power magnum loads. Heavy 38 special loads are subsonic in my lever action, and I'm not sure about 357 magnum loads but some tested on carbine length barrels were over 1900 feet per second. That's a 1000 foot per second difference in velocity.
EstablishmentFull797@reddit
Because a .357 mag rifle can fire everything from +P 125gr .357 mag loads down to .38 special subsonic wad cutters your point of impact could vary widely depending on the ammo you use.
Not a problem if you pick one load to be your precise zero and stick with that for whenever you need accuracy at 100 yards.
If you are using it for backyard pest control then make sure what ever round you choose for that is acceptably precise (e.g. if you just want to use .38 special to pop a fox in the henhouse be sure in advance that your poi isn’t that different from your longer range zero.
As far as self defense, most defensive shootings happen inside of 10 yards so rifle accuracy is basically always good enough.
mcgunner1966@reddit
I have a 10mm carbine. I shoot a holosun 507 on it. At 100 yards, I get consistent 3 in groups. The same rifle at 50 yards gets me "one hole" stacks for and 1-1.5 in. I'm sure a better shot that me could tighten it up. I've taken several deer at 50 yrds and less with it. I went with it because it uses the glock 20 mag and I love the g20. To answer your question, sure my stacks are subject to the ammo I use. I get the best performance out of federal/pmc 180gr. Hope this helps.