Why you should shoot a smaller cartridge

[Evan]

I've got a 20 Vartarg being built right now and to pass the time have been analyzing what kind of performance I should expect. I've got a 22-250 that I shoot 55gn VMax at 3500 and a 6.5 Creedmoor pushing 147ELD at 2750. The 20 Vartarg should shoot 40 VMax at 3600.

At 300yards (my preferred distance to shoot groups) If I mistake a 10mph wind as only 8mph:

The 6.5 creedmoor drifts 0.6 inches out (3 - 2.4).

The 20 Vartarg drifts 1.1 inches out (5.5 - 4.4).

The 22-250 drifts 1.2 inches out (6 - 4.8).

Factoring in barrel life to the cost, my 6.5 creed costs me 0.75 a shot (4000rnds per barrel), 22-250 costs 0.70 a shot(2000rnds per barrel), and the 20VT will only cost me 0.40 a shot (6000rnds per barrel).

This is an interesting game to play! If I play the same game with a 6BR and a 7SAUM at 1000 yards (105VLD, 2800 vs 180 VLD, 3000) and I mistake a 10mph wind as only 8mph:

The 7 SAUM drifts 7inches out.

The 6BR drifts 10inches out.

The conclusion I am drawing here is that you can't reasonably buy your way into shooting smaller. More than doubling your component cost moving from a 6BR to a 7SAUM only bought you 3 inches on a bad wind call at 1000 yards but the kicker is that bad wind call still pushed you a couple rings out either way!

 

[Evan]

I did another one that maybe will be more directly relevant to a lot of folks: 6BR vs 6BRA or Dasher (105VLD, 2800 vs 3000): 6BR is 10 inches out vs the 6BRA or Dasher at 9.3 inches.

I don't think it is worth retooling and burning an extra couple grains of powder (for those that currently have a 6BR) to gain 0.7inches at 1000 yards unless you are in the top tier of competition and can honestly say that you'll profit from that improvement to your groups.

 

[LCazador]

I don't how you calculated those barrel life numbers. Over the 50 plus years that I have been shooting it's about half of what you posted for barrel life. Of course what you accept as good barrel life and what I expect is probably way different. At any rate you never want to admit that it's costing you a $1 a shot. It may get back to your wife!! LOL!!

 

[Evan]

I don't how you calculated those barrel life numbers. Over the 50 plus years that I have been shooting it's about half of what you posted for barrel life. Of course what you accept as good barrel life and what I expect is probably way different. At any rate you never want to admit that it's costing you a $1 a shot. It may get back to your wife!! LOL!!

The 6.5 is a guess on barrel life. I haven't burned through a barrel yet. My 22-250 is loaded well down from max and shot pretty slow and conservatively. This is barrel 3 for that rifle. I'm trying to be on the high side of generous for my own sanity looking at the numbers!

 

[jds holler]

Don't forget, smaller cartridge = less green-house gasses. jd

 

[GSPV]

I get different numbers using JBM Ballistics Simplified Trajectory.

The 6.5 ELDM @ 2750, 2 mph @ 90 degrees, 300 yards is 0.9 inches.

The 20 VMax at 3600, same for other parameters is 1.8 inches.

Fundamentally, it’s twice the wind drift.

 

[Falfan2017]

I did another one that maybe will be more directly relevant to a lot of folks: 6BR vs 6BRA or Dasher (105VLD, 2800 vs 3000): 6BR is 10 inches out vs the 6BRA or Dasher at 9.3 inches.

I don't think it is worth retooling and burning an extra couple grains of powder (for those that currently have a 6BR) to gain 0.7inches at 1000 yards unless you are in the top tier of competition and can honestly say that you'll profit from that improvement to your groups.

Look at the 600 nationals results from yesterday. The difference in light gun agg between 1st place and 20th was 0.6". It doesn't take much ballistic advantage to have a serious difference in results in competition.

 

[Prose]

3600 with a 40 vmax out of the VT will probably increase the cost per shot when it comes to brass life.

 

[varmintshooter]

I like to shoot small cartridges because when I go for a walk in the field I can fit more in my pocket.

 

[K22]

Speaking from a predator / varmint hunting perspective, my favorite is the 223 Rem with a 12" twist pushing either 50 or 55 Nosler BT's. Since I also practice a lot at the range, the 223 Rem is perfect for me since it has long barrel life and is good to at least 250 yards on small target critters which cover 95% of my hunting situations.

The light recoil and economy of reloading in this cartridge is also a plus. The only negative is the you can't find a 12" twist factory offering anymore since everyone has gone heavy bullet crazy.

 

[ratbuster]

The 20 Vartarg is an incredible performer, especially when high rates of fire are called for. I believe it has inherent accuracy close to the PPC and 6BR. Stupid low recoil and barrel heat for a cartridge that can easily take small game at 400 yards, if not too windy. Only 18 grains of powder shooting 32 grain Zmax bullets (13 cents) translates into a per shot cost of approx 25 cents (including Lapua brass). 4000 to 6000 accurate rounds per barrel. It all makes for one hell of a combination.

Shoot a 223 with 55 grain bullets after shooting a Vartarg for a while and it feels like a loud, hard kicking gun.

 

[LCazador]

Don't forget, smaller cartridge = less green-house gasses. jd

Or less of a carbon foot print, especially in the throat!! Hee, hhee, ho, ho!! LOL!!

 

[LCazador]

The 6.5 is a guess on barrel life. I haven't burned through a barrel yet. My 22-250 is loaded well down from max and shot pretty slow and conservatively. This is barrel 3 for that rifle. I'm trying to be on the high side of generous for my own sanity looking at the numbers!

That isn't your own sanity you're talking about, it's called self denial!! LOL!! Sorry I couldn't resist, my apology! I never got more than 1500 rounds out of my 22/250 and even my 20 Vartag on the 3rd barrel now about 2000 is all I got. Now the one that is setting the record for me on barrel life is a 221 Fireball with a 35 degree shoulder (I have two). One of those rifles now has over 2800 rounds and doesn't show a sign of fire cracking anywhere and it's been shot hot!! Why? That 35 degree shoulder along with the 22 caliber bore moved the turbulence point inside the case! That's also why the 222 with it's long neck has such an incredible barrel life. It also moves the TP inside the case. Some other calibers with long barrel life, my 30BR, my 6PPC and my 22 Hornet Ackley. Great post!

 

[Evan]

I get different numbers using JBM Ballistics Simplified Trajectory.

The 6.5 ELDM @ 2750, 2 mph @ 90 degrees, 300 yards is 0.9 inches.

The 20 VMax at 3600, same for other parameters is 1.8 inches.

Fundamentally, it’s twice the wind drift.

That's not correct. Put in 10mph you get 3 inches and put in 8mph and you get 2.4inches. So thinking the wind is 10mph and holding 3 inches, when it is actually 8mph, results in the bullet being 0.6 inches off. The 20VT does have almost twice the wind drift, but that doesn't help people visualize what that actually means. My point is that I am spending twice as much money to make a bad shot land 0.5 inches closer to the group at 300 yards.

Look at the 600 nationals results from yesterday. The difference in light gun agg between 1st place and 20th was 0.6". It doesn't take much ballistic advantage to have a serious difference in results in competition.

If you are a national competitor, then you do what you have to do to get an edge and allot the budget required to sustain that. No argument there. I think most of us get sucked into thinking about how changing what we shoot (moving from what we have now to something different) will somehow make all the difference, and the fact is that shooting tiny groups has very little to do with the ballistic "advantage" of one cartridge over another. The difference is much smaller than I think most realize between a big boomer like a 7 SAUM and the gentle 6BR.

Or less of a carbon foot print, especially in the throat!! Hee, hhee, ho, ho!! LOL!!

Oh yes, it's an ecological wonder! 18gns of powder means you can shoot over 400 rounds on a single pound of powder. That is MANY trips to the LGS saved. The 40gn bullets use WAY less copper and lead than bigger choices. The casings use way less brass. It's honestly the earth-conscious choice and I expect everyone to praise me for making this responsible choice for our future, the future of this planet!

 

[Evan]

The 20 Vartarg is an incredible performer, especially when high rates of fire are called for. I believe it has inherent accuracy close to the PPC and 6BR. Stupid low recoil and barrel heat for a cartridge that can easily take small game at 400 yards, if not too windy. Only 18 grains of powder shooting 32 grain Zmax bullets (13 cents) translates into a per shot cost of approx 25 cents (including Lapua brass). 4000 to 6000 accurate rounds per barrel. It all makes for one hell of a combination.

Shoot a 223 with 55 grain bullets after shooting a Vartarg for a while and it feels like a loud, hard kicking gun.

I'm really excited for it. Mine will have a 26" HV barrel in a BR laminate stock of my making. Borden Rimrock BR, right bolt, left port, right eject. I can't wait to run them!

 

[Tommie]

Parker Ackley smiles...

 

[ratbuster]

That isn't your own sanity you're talking about, it's called self denial!! LOL!! Sorry I couldn't resist, my apology! I never got more than 1500 rounds out of my 22/250 and even my 20 Vartag on the 3rd barrel now about 2000 is all I got. Now the one that is setting the record for me on barrel life is a 221 Fireball with a 35 degree shoulder (I have two). One of those rifles now has over 2800 rounds and doesn't show a sign of fire cracking anywhere and it's been shot hot!! Why? That 35 degree shoulder along with the 22 caliber bore moved the turbulence point inside the case! That's also why the 222 with it's long neck has such an incredible barrel life. It also moves the TP inside the case. Some other calibers with long barrel life, my 30BR, my 6PPC and my 22 Hornet Ackley. Great post!

Only 2000 on a vartarg? You are tough on barrels!

 

[GSPV]

That's not correct. Put in 10mph you get 3 inches and put in 8mph and you get 2.4inches. So thinking the wind is 10mph and holding 3 inches, when it is actually 8mph, results in the bullet being 0.6 inches off. The 20VT does have almost twice the wind drift, but that doesn't help people visualize what that actually means. My point is that I am spending twice as much money to make a bad shot land 0.5 inches closer to the group at 300 yards.

OK. I accumulated 58 semester hours of math in college and then a MSEE. I'm pretty sure that 10-2=8. But, I ran the numbers to make sure. Result: No difference in f(10)-f(8) and f(10-8). You must be using somewhat different inputs than I am, or you're using a different trajectory calculator.
These are the runs for the 6.5 @ 10,8, and 2 mph, respectively.

 

[GSPV]

These are the 20 cal runs. 10,8, and 2 mph, respectively.

 

[jds holler]

I've been shooting smaller gentler cartridges almost exclusively for the last few years. Haven't gone elk hunting for a few, and haven't shot my 270, which I usually use when rifle hunting. -- BUT--

I've been loading shells for a friend, and getting his 7 Rem-Mag tuned up and sighted in. I hate that freaking thing!! Kicks like a mule, two or three shots, and the barrel is scorching hot and POI starts to wander.

I guess I've turned into a big pussy when it comes to big cartridges. This rifle would easily drop a cape buffalo, or even an elephant, and guys have to use them for deer and elks??!! I'd wager that most guys packing these cannons in the woods, haven't shot them enough to hit an elk at a hundred, let alone the six or eight hundred yards they squawk about. If I'm starting to sound crazy, it's because my brains are scrambled from this shoulder buster. jd