Have a RPR but got an idea

[sweetwine]

I have a Ruger Precision Rifle in 308. Very happy with it and it shoots fantastic!
But I really like to turn it into the ultimate varminter in 22-250. Has anyone ever used a fast twist
barrel (1-7) to use 77gr. SMK's? I would think you should be able to get some serious speed from the cartridge and be flat shooting.
Any thoughts on this?

 

[huntsman22]

what will it do that the 243 won't?

 

[wwb]

Too lazy to go down to the reloading room and look it up.... but will the .22-250 require a different bolt face than the .308? If so, you need more than a barrel.

 

[TBear77]

Same bolt face.

 

[Chief 101]

I have a 22-250 with fast twist and find that for me 10"-12" twist is really more practical as I use 50-55 gr bullets more than the heavies. Fortunately I had my barrel made in 9" twist so it still shoots the 50's well. When I need anything heavier I tend to use the 6mm Rem or 243 Win. I can shoot 75gr Amax bullets really accurately, just can't keep up with the 6mm's. That's my story and I'm sticking to it.
.

 

[Don Lovel]

I just loaded some 55gr Nosler Ballistic tips that will run real close to 4000fps in my .243 77MkIIV
I also have some 80gr Berger that must be making 3500fps in that rifle
.243 is way more versatile than many folks realize.
100gr Nosler Partition at 3000fps is a big game cartridge if you can shoot it well

 

[sweetwine]

No other reason other than I like the 22-250. With the RPR it would be an easy conversion with just the barrel. Thought it would have the power to push the heavier bullets flatter and longer. Don't see anything in the reloading section.

 

[Trucker]

what will it do that the 243 won't?

Fire .22 caliber projectiles of various weights at velocities over 4000 fps.

 

[Chief 101]

I say go for it...my custom 9 twist barrel shoots the 75 Amax with pinpoint accuracy but if you want to shoot longer bullets you may want to go with the 7 or 8 twist...It only limits how light a bullet you can shoot...There is plenty of loading data from Hodgdon and Nosler, and, if you go to 6mmBR forum there is a thread on loading the 22-250 that will cover heavier bullets, just research any forum data before you try it as there are ego's writing formulas and not scientists.
For Hodgdon data you will have to google it yourself
http://www.nosler.com/nosler-load-data/22-250-remington-fast-twist/
http://forum.accurateshooter.com/threads/need-pet-loads-for-upcoming-22-250-cartridge-guide.3754283/

Huntsman, 6mm bullets at over 4000fps is easily attainable but hi numbers like that kill barrels fast...I know because I've killed a few 22-250 barrels...its only a number

 

[wwb]

I have no dog in this fight, but I've always worked for accuracy (group size) rather than velocity. I've also found that something a bit under the max load is generally the most accurate.

I don't care if you're pushing over 4,000 fps or not, you're still dealing with trajectory. As long as you know where to hold for a particular range, velocity doesn't matter (other than its effect on energy).... and accurate range estimation without a rangefinder is a skill that few possess. Also, if long range energy is a concern, a heavier bullet is the way to go.... lighter bullets may start out faster, but they shed velocity much quicker.

It's okay to say you broke that magic 4,000 number but if you step back and look at the practicality of it, like Chief 101 said, "It's just a number". A friend of mine once had a .264 Mag that he bought only because of the impressive numbers (which, as it turned out, were "stretched" a bit). After several years and a new barrel, he sold it and bought a .270 saying, "The .264 won't do anything the .270 can't." - with age comes wisdom.

 

[gtxmonte]

While I like a 22/250, if I was building an "ultimate varminter" that wouldn't be it. You could blow it out to a 22/250 AI. Or you could go 220 Swift, or even 220 Swift AI. I have heard of those at 4400. Also the 243 AI can be a burner

I highly disagree with wwb's statement that "velocity doesn't matter". It matters greatly in terms of accuracy. While it is true that faster bullets shed velocity faster, it is also true that while supersonic, faster bucks the wind better.

Easy test.........assuming a rifle is just as accurate with a 55gr bullet at 3600 as it is with same bullet at 4000 on a calm day. Do the same test with a little crosswind and then tell me velocity doesn't matter. There is a reason BR shooters generally use hot rounds.

Now you might say, well it still groups good, just has some wind drift. OK..........how good are you at reading a crosswind at long ranges and being able to accurately dope for it. Some of the best shooters in the world struggle with this at times. If I can load it hotter, make it resist drift, I am going to do it and so will most everyone else.

 

[wwb]

........
I highly disagree with wwb's statement that "velocity doesn't matter". It matters greatly in terms of accuracy. While it is true that faster bullets shed velocity faster, it is also true that while supersonic, faster bucks the wind better.

Easy test.........assuming a rifle is just as accurate with a 55gr bullet at 3600 as it is with same bullet at 4000 on a calm day. Do the same test with a little crosswind and then tell me velocity doesn't matter. There is a reason BR shooters generally use hot rounds.

Now you might say, well it still groups good, just has some wind drift. OK..........how good are you at reading a crosswind at long ranges and being able to accurately dope for it. Some of the best shooters in the world struggle with this at times. If I can load it hotter, make it resist drift, I am going to do it and so will most everyone else.

Sorry, but I take issue with the above. My "varmint" experience is all .223 Rem, but the same thing applies to any similar caliber.

We're talking "varmint" rounds here, not .38 Special. Any "varmint" round would have to be 1,000+ yards out there before it goes subsonic, so let's forget the "supersonic" business. Faster is less influenced by a crosswind only for the same bullet; a lighter bullet is more influenced by a crosswind than a heavier bullet. As it turns out for any given caliber, the change in velocity (which determines flight time and therefore wind influence) from a light bullet to a heavier bullet is almost exactly offset by the heavy bullet being less influenced by a crosswind. The net result is an insignificant difference between the two - check any ballistics table or ballistics calculator. My experience bears this out.

I know a couple hard-core benchrest shooters... believe me, those guys load for group size and NOTHING else. If you can load it faster and still get a the same size group, they will do it, but if the group opens up at all, it's a deal-breaker.

Since you're so hung up on velocity and advocating light bullets, go back to the ballistics tables or calculators and see what happens when you get out to 400 yards or more. I ran a couple examples through my calculator using the bullet mfr ballistic coefficient:

.223 Rem
55gr Sierra BTHP muzzle 3240 400 yd 1850
69 gr Sierra BTHP muzzle 2950 400 yd 1833

.243 Win
85 gr Sierra BTHP muzzle 3300 400 yd 2140
100 gr Sierra BTHP muzzle 2960 400 yd 2145

Once you get beyond 400, the heavier bullet is now the velocity king. The exact yardage at which this happens will vary depending on the caliber, the bullet selections being compared, and the starting velocities, but it always holds true. And if you're shooting coyotes instead of paper, the energy advantage of the heavier bullet is worth something.

 

[gtxmonte]

........
I highly disagree with wwb's statement that "velocity doesn't matter". It matters greatly in terms of accuracy. While it is true that faster bullets shed velocity faster, it is also true that while supersonic, faster bucks the wind better.

Easy test.........assuming a rifle is just as accurate with a 55gr bullet at 3600 as it is with same bullet at 4000 on a calm day. Do the same test with a little crosswind and then tell me velocity doesn't matter. There is a reason BR shooters generally use hot rounds.

Now you might say, well it still groups good, just has some wind drift. OK..........how good are you at reading a crosswind at long ranges and being able to accurately dope for it. Some of the best shooters in the world struggle with this at times. If I can load it hotter, make it resist drift, I am going to do it and so will most everyone else.

Sorry, but I take issue with the above. My "varmint" experience is all .223 Rem, but the same thing applies to any similar caliber.

We're talking "varmint" rounds here, not .38 Special. Any "varmint" round would have to be 1,000+ yards out there before it goes subsonic, so let's forget the "supersonic" business. Faster is less influenced by a crosswind only for the same bullet; a lighter bullet is more influenced by a crosswind than a heavier bullet. As it turns out for any given caliber, the change in velocity (which determines flight time and therefore wind influence) from a light bullet to a heavier bullet is almost exactly offset by the heavy bullet being less influenced by a crosswind. The net result is an insignificant difference between the two - check any ballistics table or ballistics calculator. My experience bears this out.

I know a couple hard-core benchrest shooters... believe me, those guys load for group size and NOTHING else. If you can load it faster and still get a the same size group, they will do it, but if the group opens up at all, it's a deal-breaker.

Since you're so hung up on velocity and advocating light bullets, go back to the ballistics tables or calculators and see what happens when you get out to 400 yards or more. I ran a couple examples through my calculator using the bullet mfr ballistic coefficient:

.223 Rem
55gr Sierra BTHP muzzle 3240 400 yd 1850
69 gr Sierra BTHP muzzle 2950 400 yd 1833

.243 Win
85 gr Sierra BTHP muzzle 3300 400 yd 2140
100 gr Sierra BTHP muzzle 2960 400 yd 2145

Once you get beyond 400, the heavier bullet is now the velocity king. The exact yardage at which this happens will vary depending on the caliber, the bullet selections being compared, and the starting velocities, but it always holds true. And if you're shooting coyotes instead of paper, the energy advantage of the heavier bullet is worth something.

If they can load it faster and get the same group size they will....Why would they do this if velocity doesn't matter...........that's what you said above, velocity doesn't matter. I am saying it matters greatly. I am not hung up on anything and never suggested light bullets, but frankly some of your info is not correct

The BC and the velocity is what matters, not bullet weight, as far as accuracy. If two bullets have the same BC and are fired at the same velocity, doesn't matter if one is 100gr and the other 200gr, they will both have the same wind drift. So just saying a lighter bullet is more apt to be effected by wind is not correct.

This is proven all the time in 1000 yard matches. The current group and aggregate bests are held by 6MMs of various types.......NOT 30 cals firing 210gr Match Kings. Match shooters will shoot them as fast as they can and not suffer accuracy. So the point is, if velocity doesn't matter, why do we do that?

Speaking of 30 cals.........why are long range MATCH 30 cals 300 Win Mags and 300 RUMs instead of a 30/06? Easy, because you can smoke those bullets out there a LOT faster.

So you can take issue with my statement all you want, but the faster you can be and the accuracy not suffer, the better off you are. That's a proven fact