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Jesse's Hunting > Gun Room Articles > Gun Room Archives > Getting the Most from Your .22 Magnum
Getting the Most from Your .22 Magnum
Andy Moe - JHO ProStaff
- San Diego, CA
June 25, 2005
For weeks, my friend Jack had been nagging me with endless questions regarding the 17 Hornady Magnum Rimfire (HMR) and the 22 Winchester Magnum Rimfire (WMR). The local sporting goods store was having a sale on the Savage Model 93 Heavy barrel in both calibers. He wanted to know which would suit him best, but lacked the practical experience to make the choice on his own.
Like many relatively new shooters, Jack’s knowledge of ballistics was limited and he’d had no chance to shoot either of these fine cartridges for himself. When he found out I was a shooter –and shot both the 17HMR and the 22WMR- he seized every opportunity to wring The Truth out of me.
I decided that letting him shoot both cartridges in the field was the only way to give him the answers he wanted, so I invited him out to my favorite ground squirrel haunts for a shoot. There’s nothing like first hand experience, right? Besides, what could I really tell him? Both cartridges have their strong and weak points and there is no simple answer to the “which is better” debate. Fans of both cartridges line up on either side of the literary fence. Personally, I like them both and believe they both have a place in the field. I’m not about to step into the middle of 17HMR vs. 22 Magnum fray.
At the ground squirrel fields we set up our gear and I ran Jack through the loading and safety procedures. Luckily, he’d had a bit of experience shooting 22LR while growing up on a farm, so he wasn’t a complete stranger when it came to firearms and their handling. It was a good day for shooting ground squirrels. The temperature was around 100 degrees and the weather was hazy and overcast. I positioned my eager companion in an area that afforded shots from 25 to 150 yards, explaining that with either cartridge, I felt the maximum range for a humane kill on these little critters fell somewhere near the 150 yard mark.
In the 17 HMR we were using the Hornady V-Max 17 grain round I’d chronographed earlier that morning at 2608 ft/sec. The 22 WMR load was the Federal 40 grain FMJ which had been clocked at 1957 ft sec the previous day. We talked about the differences in trajectory and drift as we waited for the squirrels to make their appearance. We didn’t have to wait long.
The low speed and looping trajectory of the 40 grain 22 Magnum load seemed to put Jack off a bit so he elected to start his shooting day off with the faster and flatter 17HMR. His first kill was at 80 yards. A tawny colored squirrel stood on a mound to survey the alfalfa field below and Jack covered him with the 17 HMR. The results were explosive. His next shot was at 155 yards. I told him that with the 100 yard zero of the 17HMR he should hold over about two and a half inches. Again, the bullet found its mark. The results were less dramatic but the squirrel was just as dead. Another squirrel appeared next to his fallen comrade and I handed Jack the 22WMR. When he asked me where he should hold I advised him to set the reticule about three inches high. He settled in behind the scope but then stiffened and turned to me, “Wait a minute! You mean there’s only a half-inch of difference in the trajectory? That can’t be right.”
Well, it is… And it isn’t.
When sighted in at 100 yards, the 17HMR load has only two and a half inches of drop at 150 yards. This is outstandingly flat shooting for a rimfire and one of the reasons this cartridge is so popular. Most 22 WMR loadings shoot nowhere near as flat. With the Federal 40 grain 22 caliber bullet at 1957 ft/sec the drop is more than twice that of the 17HMR, falling about five-inches below the line of sight. So, did I give Jack some bum advice? No, because I didn’t sight in the 22 magnum for 100 yards. For this outing I upped my zero to 125 yards, while leaving the 17HMR sighted in at the more traditional 100 yard mark. The difference in field shooting is dramatic.
Point of Aim vs Impact
The 17HMR drop at 150 yards is shown here. |
22 WMR Drop at 150
Note the drop in the 22 WMR at 150 yards. Remember, this rifle was sighted in at 125 yards instead of 100. |
The accompanying charts were generated by my Point Blank Ballistics software. In them you can see the graphic evidence of the change that shifting my zero a bit further down range had. While the 100 yard zero for the Federal 40 grain load needed a 5” hold over to connect at 150 yards, the same load zeroed at 125 yards needed only 3 inches hold over. The 17HMR certainly remains king when it comes to shooting flat, but this added bit of elevation with the 22WMR narrows the gap. And to boot, the 40 grain bullet arrives with about 20-percent more energy than the 17HMR’s seventeen grain pill. That’s the ace-in-the-hole that most 22 magnum shooters rightly draw when facing a 17HMR fan who just played the trajectory card.
Trajectory of 17HMR, zeroed at 100 yards.
Trajectory of 40gr .22WMR, zeroed at 125 yards. The 150 yard marker isn't called out in the graph, but you'll note that the bullet shows about a 3" drop at that point.
Ah! But there’s no such thing as a free lunch when dealing with ballistics, and losing that 2-inches of drop at long range is paid for up close. Every shooter seems to be able to mentally digest a little bit of “hold-over” in the field but it’s a little harder to get a handle on “hold under” –and that’s what a 125 yard zero using this 22WMR load generates when shooting at closer ranges. At 75 yards you now strike 2.4 inches above the point of aim. It’s a mental adjustment, but you get used to it quite quickly. I simply place the cross hair on the lower third of a standing squirrel, or along the belly of a prone squirrel, and the lights go out.
Hornady Magnum shooters of course, need no hold over on ground squirrels until the range extends past roughly 130 yards. At that point, the 100 yard-zeroed seventeen falls 1.14 inches below the line of sight. On these skinny squirrels you need to merely hold on the upper chest to plant a round in the midsection. At 150 yards you simply set the reticule on top of the head and squeeze, letting Hornady’s engineering take care of the rest.
When the 22WMR shooter switches to a lighter bullet, such as the CCI/Speer “TNT” 30 grain HP, then the ballistic numbers start getting really close. The Speer bullet with a ballistic coefficient of 0.090 and a muzzle velocity of 2350 ft per/ second, has only a 2.4” drop at 150 yards when sighted to 125 yards, with a 1.4” hold under at 75 yards. If your rifle shoots these bullets well then you are in business. Unfortunately, due to the low B.C. of this bullet the velocity bleeds off so quickly that, by the time it reaches 150 yards, it is within a pound or two of having the exact same energy as the 17 grain Hornady bullet.
On the other hand, if your 22 magnum rifle likes the Remington Premier 33 grain Accu-Tip then you’re really in luck. With a ballistic coefficient of 0.140 it can really keep on trucking when shot at 2050 ft/sec. and zeroed for performance at 125 yards. Then the drop at 150 yards is a mere 2.31 inches. That’s a tad less than our 100 yard zeroed, 17HMR V-Max load has at that range. And the Remington arrives packing 135 ft/lbs of energy. Hold under is 1.6 inches at 75 yards. Most of my 22WMRs really like this bullet and it’s the #1 choice when longer shots are in order.
I already mentioned that my purpose here isn’t to pitch one cartridge against the other and I’m not going to rehash every argument proponents of these rounds might bring up. I do want to mention wind drift, though, because Jack and I experienced a bit of it during our Saturday afternoon outing. The 17 HMR data lists a 7.5 inch cross wind drift at 10 mph, the Federal 40 grain load shows to have a 12.5 inch deflection under the same conditions. The CCI / Speer “TNT” 30 grain has a bit less at eleven inches, and the Remington Premier has the least of all the 22WMR loads mentioned at just over nine inches. Wind drift is less with the 17 Hornady round but we discovered it just doesn’t take much of a breeze to blow any of these rimfire bullets off of a skinny ground squirrel at 150 yards, and once you’re holding off in a cross wind it really doesn’t matter if it’s 7.5 inches or 12.5 inches: It’s in the hands of the wind gods once the priming ignites. We missed just as many squirrels due to the wind shooting the 17 Hornady Magnum as with the 22 magnum.
Jack took that next squirrel with the 22 magnum and several others during the day with that same rifle. He seemed to favor the laser-like 17HMR and for ground squirrels. It may be the best round out there. For cost and utility though, my friend recognized that the 22WMR is hard to beat; especially when you’re willing to readjust your zero to extend your range. At the end of the day poor Jack was still undecided as to which round was best and he went to great lengths to let me know that he wasn’t happy about it. When I suggested that he needed to shoot both cartridges he cocked his head, raised an eyebrow and smiled.
Peace and quiet! Finally!
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