The Mighty 20-250!
I got the itch for a larger, faster 20 caliber cartridge when I missed a coyote with my beloved first born, the 20 caliber Bobcat (20-222 Imp). The coyote was hunting mice in a hay meadow at 350+ yards. I figured I was asking a lot from the little bobcat when I pulled the trigger and I was right. Even holding a little over the coyote the bullet fell short. Darn, one lucky coyote lived to hunt mice another day.
I thought about the 20 Tactical but the water capacity of the case is only slightly more than the 20 Bobcat. The obvious choice was the 22-250 case, just simply necked down to 20 caliber.
I called Dave Kiff at Pacific tool and we discussed the options for this new cartridge. To make a long story short, I ended up ordering two reamers; 20-250 and 20-250 Imp, both with tight necks and minimum tolerances.
The first 20-250 was built for a long time client of mine, Jim Remza. Jim wanted to use a Sako L461 action, a 26” Pac-Nor Super Match, 3 grove, 1 in 12 twist, #.4 contour barrel.
Jim has been very successful with
his 20-250. He used it on Coos Deer in
20-250 Load Data:
Bullet Powder Charge Velocity
40 gr Berger H380 42 4000
40 gr Berger IMR 4064 37 4093
50 gr Berger H380 40 3752
50 gr Berger Win 760 38 3752
50 gr Berger IMR 4064 35 3856
All load data should
be used with caution. Always start with
reduced loads first and make sure they are safe in each of your guns before
proceeding to the high test loads listed.
Since Weaver Rifles has no control over your choice of components, guns,
or actual loadings, neither Weaver Rifles nor the various firearms and
components manufacturers assume any responsibility for the use of this data.
20-250 IMP.
I went ahead and built a 20-250 Imp with a 40 degree shoulder for myself. I used a Pac- nor Super Match, 3 grove, 1 in 12 twist, number 3 contour barrel finished to 26 inches. I had an old Remington 600 action that I bought from a fire sale. And when I mean a fire sale I mean a fire sale. The barreled action was in a house fire and was rusted badly. I bought it for $40 thinking I could part it out.
I had the action and bolt hardness tested to
find out if the fire had tempered the steel. As it turned out, the action was
not near the heat of the fire, and hardness was fine. I removed the rust and
cleaned it up, putting on a
The results of the 20-250 Imp were beyond my hopes and expectations. The fire form loads were as accurate as any hunting rifle I have ever shot. The velocity of the 40 and 50 grain Berger bullets were well above the 4000 feet/second range.
I found out in a hurry that the max loads were hard on the primer pockets, after 2-3 firings the primers just fell out of the pockets. I came up with a plan that I thought would prolong the fit of the primer pockets. I would try the old Remington BR Cases with small rifle primer pockets..
Forming the 308 BR cases down to 22-250 cases was tedious and time consuming but the results were worth while. The primer pocket failure rate, with max loads, dropped 80% with small rifle primers and the velocity increased a little.
Forming process:
20-250 IMP
Load Data:
NOTE: MAX LOADS REDUCE POWDER CHARGE 20%
Bullet Powder Charge Velocity
40gr
Hornady
33gr Hornady IMR 4350 42grs Fire Form
36gr Berger
40gr Berger
40gr Berger IMR 4320 42.grs 4492
40gr Berger N135 35grs 4267
40gr Berger N540 40grs 4401
40gr Berger N160 45grs 4264
40gr Berger Varget 41grs 4352
40gr Berger IMR 4350 45grs 4353 most accurate load
40gr Berger IMR4064 43grs 4487
50 gr Berger N560 43grs 3958 most accurate load
50gr Berger N160 44grs 3955
50gr Berger H4831 43grs 3972
50gr Berger IMR 4831 45grs 4088
50gr Berger MRP 45.5grs 4014
50gr Berger N165 45grs 3953
50gr Berger RL 22 46grs 4078
20-250 IMP Load Data:
Remington BR Cases formed to 20-250, then fire formed. Federal 210 primers, Pac Chronograph placed 12’ from muzzle.
NOTE : MAX LOADS REDUCE POWDER CHARGE 20%
Bullet power charge velocity
36gr Berger IMR 4064 43grs 4673
36gr Berger Winchester 760 47grs 4558 most accurate
36gr Berger N540 40grs 4471
40gr Berger IMR 4064 44grs 4630
40gr Berger
40gr Berger N540 40grs 4380
40gr Berger IMR 4350 40grs 4387 most accurate
45gr No-Name IMR 4350 45gr 4288 most accurate
All load data should
be used with caution. Always start with
reduced loads first and make sure they are safe in each of your guns before
proceeding to the high test loads listed.
Since Weaver Rifles has no control over your choice of components, guns,
or actual loadings, neither Weaver Rifles nor the various firearms and
components manufacturers assume any responsibility for the use of this data.
I have favored a 22 Cheetah for my coyote hunting for almost 15 years but now when I reach in the safe and pull out a coyote rifle, the 20-250 Imp is the rifle of choice.
Shots on coyotes at close range, under 200 hundred yards, the 40gr Bergers tend to rip some sizeable exit holes. So I went to the 40 Hornady bullets and most of the exit holes are small or non-existent.
Many of my clients want to stay away from the 17 and 20 calibers because they think the 20 is more sensitive to wind deflection. Yes, that is true in a way. The lighter the bullet is more sensitive to wind than a 55gr 22 cal bullet with the same velocity. But another factor needs to be put into the equation. Speed, the longer a bullet spends in flight, the more time the wind has to effect deflection. So let’s compare a 22-250 with a 55gr bullet traveling at 3600 f/sec. and a 20-250 40gr at 4000f/sec. The wind deflection will be about the same because flight time is shorter with the 40gr .204 bullet.
To demonstrate the accuracy of the 20-250 Imp under hunting conditions, at various ranges. I shot over the hood of my truck using an Uncle Mike's Bag. A windy day, winds gusting 10-15 mph with a temperature in the teens. The target demonstrates that the 20-250 Imp is an excellent varmint cartridge, only dropping 1 and 1/2 inches from a 200 yards zero.
Jim Remza with 20-250 referred to above. Built on a Sako Action with a Pac-Nor, 3 groove, 1 in 12 twist, 26" Barrel. This deer was shot with a 50 grain Berger.