What is the the most flat shooting cartridge yall can think of?

[Horse1]

It's on my to do list

257STW worth a look too depending on what you can find for brass. Basically the same thing minus the double-radius shoulder.

 

[DUCKMAN11]

How are the winds?

0mph to 50mph back to 0mph all in the same day and from every direction but east usually

 

[DUCKMAN11]

257STW worth a look too depending on what you can find for brass. Basically the same thing minus the double-radius shoulder.

There are more efficient cartridges out there that will duplicate 257wby and likely 257stw without having to burn all that powder and deal with a belt.

A friend of mines father shoots a 257stw and I think his load is somewhere in the neighborhood of 86gr of powder behind a 100gr bullet for 3800fps. It's no slouch but it takes a lot to feed a fire breather like that.

 

[Calvin45]

257STW worth a look too depending on what you can find for brass. Basically the same thing minus the double-radius shoulder.

Oh I've considered it. But I'm probably gonna go .25-300 wby for a few reasons - or just leave the existing barrel alone as the 25-06 AI it currently is. It's a very lightly used (throat in great shape) ultra heavy 32 inch bartlein stainless barrel I got on an auction. Just a barrel with a tentative plan for now, things gonna be tight for a bit but within the next few years planning to go ahead and do a cheap build off a savage long action as a single shot, totally impractical and just a pure exercise in hot-roddery.

I haven't fully ruled out either of my other contenders but if I do rechamber this barrel it will be to either a .25-300 wby, .257 STW, or a .25-300 RUM/.257 Allen magnum type cartridge. I've ruled that it will be a full length magnum to clean up the existing 25-06 ai chamber without any setback required, and with the standard .532 (I think) magnum bolt face. So one of these three I mentioned will fit the bill.

It is a 10 twist and as such the 130+ grainers are off the table. If they were not I'd probably go with the full RUM case. But I have my doubts about it beating the wby/stw case by much if at all with 115 grain bullets and lighter just seeing how Fast we can go. I could be wrong tho.

There are a few reasons why the .25-300 wby really is the direction I'm leaning HARD towards over the .257 stw.

1. Brass. This is the big one. Peterson makes 6.5-300 wby and .300 wby brass. Neither Peterson, lapua, or adg make stw brass. Norma makes brass for both, it's not as tough but very volumous and consistent, good stuff just don't get the case life at high pressure. But I will say even there Norma 300 wby brass is waaaaay more findable than the 7stw stuff. And I know you could size and fire form brass from .300 weatherby or .300 Hh or others to make stw brass…this barrel will be short lived as it is, if it requires fire forming it's not happening.

2. Dies.

But anyway, the main idea is that it would be sooooo easy to just run 6.5-300 PETERSON brass to neck and shoulder size in my .257 weatherby dies which I already have. Could also run it through my 450 ackley dies with the expander/decapper removed to resize the full length of the body, no new dies needed.

3. I like the weatherby shoulder and believe it does have some benefits. I don't know that I believe it somehow increases velocity as Roy claimed, I think it's been pretty well proven it doesn't matter either way (much the same as how the few extra grains in an ackley improved case don't magically make it 300 fps faster AT EQUAL PRESSURE) but what I do think it does is sort of smooth out the pressure curve and most importantly I see a strong case to be made that this shoulder geometry should actually help to alleviate the powder bridging issues that often plague extremely overbore sharp shouldered smallbore magnums. And it looks killer, the full length weatherby magnum case is curvy with long legs haha. I'd plan to give this the generous weatherby freebore treatment too. It'd be a pretty different animal than the 6.5-300 despite only being .007" smaller bore because of the 10 twist and greater freebore I think I'll run…this will be a dedicate light bullet going stupid fast just for fun gun. The ultimate point blank ranger.

Now the weak point is the reamer…dedicated .25-300 wby reamers aren't something in many gunsmith's inventories or available as rentals. They are pricey and have wait times. HOWEVER.,..I've never done this before but am actually wondering if it'd be as simple as using the kind of floating chamber reamer that has interchangeable pilots and just "interchanging" the pilot on a readily available 6.5-300 wby reamer with a .257" pilot?

 

[choprzrul]

120mm with depleted uranium sabot with muzzle velocity right at 5000 fps?

 

[Calvin45]

120mm with depleted uranium sabot with muzzle velocity right at 5000 fps?

That probably is the actual winner haha…for technical "cartridge" anyway. The electromagnetic rail gun is faster but, alas, does not use cartridges at all (or work particularly well for long term use…and requires and dang nuclear powered generator to adequately electrify if on a ship or anything mobile as nothing else remotely portable generates enough juice ….ill take the cartridge guns thank you!)

 

[Paladin300]

22-250 AI/FT is the flattest shooting cartridge I own to 500 yards. It will stay in a 4" circle to 308 yards, according to my ballistics calculator, with a 50 gr BTV with a BC of. .267. It will launch them at 4000fps from a 27in barrel. Mine has a 27" Krieger with a 1/8 twist. Carries just over 850 ft lbs of energy to that range. It is more than enough for Coyotes. It will drop 5 rounds in the same hole at 200 yards, though to achieve that I have to drop my velocity to just over 3800 fps. I tend to hold over or dial and zero at 100-200 yards. So I had to play with it to see what MPBR would be. Zero would be 266 and you would be 1.49 high at a 100.

I would suspect, as has already been mentioned, that the 257 wby is the flattest shooter to 500. Once you move past 500 the bigger cartridges with the higher BCs take over.

You would really be splitting hairs between any of the fast flat 22-25 calibers. No more than probably 5-10 yards difference in MPBR. It really depends on the rifle and barrel configuration, bullet and powder combination. The same exact barrel specs can produce different result from barrel to barrel from the same manufacturer, as much as 50 fps. Additionally, if you and your rifle can't shoot .25-.5 moa (most individuals need a fairly light recoiling rifle to achieve this) all the speculations and calculations go out the window. Bullet construction matters too. Most varmint bullets if you spin them too fast will explode north of 4000 fps. Your 25-06 AI especially if you are already set up to load for it would be right there in the mix. 300 yards on a 4" plate for MPBR is about as good as it gets for consistency's sake. JMTs.

 

[Dragoon300]

I have always loved the 220 Swift with a B&L Balvar 8, that my Dad bought for Fox hunting in 1958. I grew up shooting that gun at 200 yards using roofing nails in a board for targets! (His idea) And he was capable of that too! He liked the fact that if he could put the cross hairs on the Fox it went down, and he could see it drop before hearing the shot go off! (His words)

I just ran the numbers on my 30" Lilja barreled 223 WSSM @ 4150 FPS with Nosler Balistic Tips. My AB app shows the following with a 305 yard zero:
-2.0" @ 17 yds.
+2.0" @ 192.5 yds.
-2.0" @ 349 yds.
Not too bad for small critters.

 

[FEENIX]

0mph to 50mph back to 0mph all in the same day and from every direction but east usually

LOL! This is one of the reasons I prefer heavy/high BC bullets. Below in 2015, while antelope hunting.

 

[Phil Rizzo]

Question: with a heavy high BC bullet for caliber and large case, why choose a barrel less than 26"?
More speed counters breeze and flattens the path as you well know. I'm curious is all!

 

[FEENIX]

Question: with a heavy high BC bullet for caliber and large case, why choose a barrel less than 26"?

For preferred suppressed hunting/shooting.

More speed counters breeze and flattens the path as you well know. I'm curious is all!

Yes, but I also have rifles with 26-30" barrels, and I can use my suppressors. It just depends on the mood of the day.

6.5 CM 24" barrel

.257 WBY 22"

.264 WM 26"

.30 LARA 27"

Same suppressor on all of them.

 

[Horse1]

Question: with a heavy high BC bullet for caliber and large case, why choose a barrel less than 26"?
More speed counters breeze and flattens the path as you well know. I'm curious is all!

Handiness. I've got a 1:7 bbl on the way for a Kimber Montana that will become a 22Creed. It will be finished @ 22".

 

[Phil Rizzo]

I hunt out of enclosed stands sometimes, use UTV's with cabs and hunting trucks to get there, but still value performance over convenience.
Just personal preference. No wrong answers.

 

[jessej]

There are more efficient cartridges out there that will duplicate 257wby and likely 257stw without having to burn all that powder and deal with a belt.

No replacement for displacement.
There's no substitute for cubic inches.

That probably is the actual winner haha…for technical "cartridge" anyway. The electromagnetic rail gun is faster but, alas, does not use cartridges at all (or work particularly well for long term use…and requires and dang nuclear powered generator to adequately electrify if on a ship or anything mobile as nothing else remotely portable generates enough juice ….ill take the cartridge guns thank you!)

It's a little heavy to pack around in the hills.