Working up a load for your small bore gun

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Working up a load for your small bore gun

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WORKING UP A LOAD FOR YOU SMALL BORE GUN
By Steve Mooney

Now before you think I’ve gone completely mad, let me explain. I have had many shooters ask me what brand of 22 ammo I shoot in my small bore guns and I’ve seen numerous postings on the various website message boards asking similar questions. What ammo is the most accurate for a Buckmark or a Ruger revolver, etc? If you think there is one brand over another that will shoot more accurately you are correct. The only problem is that it not only depends on the make and model of the gun, but each individual gun or barrel. I have two 10” Thompson Center Contender 22 Match barrels that are both very accurate; however they are the most accurate with two completely different brands of ammo.
The secret to an accurate small bore gun is not much different from getting the most out of your center fire gun. It involves finding a bullet and powder combination that it likes the best. Except in the case of your small bore gun the ammo is already loaded for you. Now that being said, there was a time back in the day when men braver than I would carefully pull bullets from 22 rimfire cartridges and swap out powder or bullets then gingerly reassemble them, but current IHMSA rules restrict that practice these days. So, the only way to really find out is to conduct some good old fashion scientific “trial and error.”
Many shooters are of the opinion that the more expensive the ammo the better the groups it will shoot and in some cases that is true. However, I have found over the years of playing this game that there are many instances where you can get some very accurate results without having to mortgage the farm to buy a case of 22 ammo. I have somewhat of a budget when it comes to shooting and I try to work within my means as much as possible. So the less I spend per round means more rounds to shoot per dollar, which equals much more fun. I have found the best way to approach this “experiment” is to first set some parameters. There are three main factors I consider when choosing a brand of 22 ammo. First is the accuracy in that particular firearm at 100 yds. Second is the cost of that accuracy in relation to all the brands tested. Third is not as important as the first two, but still a factor and that is trying to use similar ammo for multiple guns. Of the six small bore categories that I regularly shoot I usually can get by with just three types. For shoot-offs or Regional matches I’ll add a fourth.
So let’s look at the first two parameters more closely. I always test ammo at 100 yards or meters. That is the maximum distance for small bore and that is where you need to see what the bullet is doing. I have found many times that ammo that shoots dime size groups at 50 will sometimes open up to 12” or more at 100. If you’re testing at any closer distance you could be just wasting time and ammo. Being somewhat budget minded brings into play the second parameter. I like to test a variety of different brands but still have my budget to think of. This is where you have to make some decisions. How much are you willing to spend and just how accurate does your pistol have to be for our game? If you asked a dozen people you would most likely get a dozen different answers so I will just give you my criteria. I like to do most of my testing with what I refer to as “mid-priced” ammo. I usually avoid the bulk pack bargin basement varieties that most manufactures offer. Mainly because I have found it to be very inconsistent from batch to batch. It might test great at first, but then the next brick or bulk box you buy is very different or you may get a few “fliers” off and on. Although I know of a few shooters that use it, and still do ok with it. I am also too cheap to shoot the super high end stuff on a regular basis. I have one pistol that groups well with a mid-priced brand, WOLF Target, but produces incredibly small groups with Eley EPS. I shoot the WOLF 90% of the time but for big matches and shoot offs I’ll pull out the pricey stuff. So how accurate is accurate enough? If I can find a mid range ammo ($4 to $6 dollar for a box of 50) that will consistently give me groups close to 2” at 100 I’ll call it good. If it’s an UAS or U gun where there is a good possibility of having to “shoot off” then I will also test for ammo that would hopefully get me in the 1” or less range. This will be a personal choice for you based on what categories you shoot and what your demands are. If you are happy with 3” groups and are just shooting the standard small bore targets then go with it. If you plan to shoot the “runts” (1/5 scale) or get into shoot off situations a lot, then you are going to need to get the most accuracy you can from your pistol. When considering the third parameter I will usually just start my testing of a new gun or barrel with ammo brands that I am currently using in other pistols. If I get acceptable accuracy then that’s a plus. If not, then it’s back to the drawing board and I start testing other brands and types.
So how does one go about finding the right ammo for a particular pistol? I try and remove as many of the “variables” as possible. Some, but not all, variables can be: wind and weather, gun movement, target visibility, trigger control, and bore condition.
The first item on the list, wind, can be a real accuracy killer. I try and do my testing all on the same day and in the same weather conditions, preferably a nice calm clear day. If you test one brand with a strong wind and another in calm weather, you really can’t be sure if the group will be an accurate representation of that ammo. What if you have a great 9 shot group and get a flier, was it a gust wind or the ammo? Remove the variables! Although most rim fire ammo is not real temperature sensitive, extreme temperature changes can affect performance also, so I try and test in weather that is similar to what I will be shooting in. If you do all your testing in the cold of winter, but do most of your shooting in the hot summer months you may get some inconsistencies.
To eliminate gun movement I use a combination of sand bags or an adjustable front rest and a sand bag under the grip. If you use an adjustable rest be sure it has some way to secure the forend of the pistol. Use either a “rabbit ear” type bag or a soft rubber “V” notch to keep it free of any movement. The object here is to remove as much tilting, side to side, and up and down movement as possible. I prefer to totally secure the pistol with sandbags as in the photo. It holds well and allows great consistency from one shot to the next.
For target visibility I recommend mounting the highest magnification rifle scope you own on the pistol with a good solid base and ring system. Since the recoil of the 22LR is minimal a rifle scope can be used and has definite advantages over using open sights or even a pistol scope. Higher magnification allows you to be more accurate in sighting the same point on your target for each shot. I like to use a target that either has a very small dot to aim at or one that has vertical and horizontal lines on it to line up with the crosshairs in the scope. Again, being consistent shot to shot is paramount.
Trigger control can make a huge difference in your ability to consistently obtain the same point of aim shot after shot. Be certain that you are not moving the gun while squeezing the trigger and be very diligent to hold the gun in the same way with as little pressure as possible for each shot. Having a fairly light trigger with little or no creep is a must. I had a friend that was doing some ammo testing on his Contender. He called and said he had tested over ten different types (even some high end brands) and wasn’t getting any of them to group much better than 5” to 6” at 100yds. He asked if I would give it a try with my set up. I met him at the range and after the first shot from his gun realized the problem. His pistol had about a 5 pound trigger pull with a lot of creep that felt like dragging a lead brick over cobble stones. We swapped his barrel to one of my frames and the groups immediately tightened right up.
In regards to bore condition, it can be debated for months as to whether or not to clean, how to clean, and what to clean with, for small bore barrels, but for ammo testing I am more concerned about consistency rather than method. I will explain the method I use when testing and why I do it. I think, whether you believe in cleaning or not, it is important to start with the same “condition” of barrel with each brand or type of ammo you are going to test. To do this I clean the chamber and bore with a brush and solvent, then run 4 or 5 patches down it. I will do this, keeping the same procedure each time; at the end of testing one brand, before starting to test the next. I then shoot 3 or 4 “fouling shots” with the next brand before putting it on paper for group. Each type or brand of ammo can have a different lube, lead alloy, plating, etc. and I want to be certain that I am testing just that one type without any residue left from the previous one. I like to shoot at least 10 shot groups as this will give you a very good idea of what you can expect out of that particular brand. If I am testing many different types of ammo I will start off at 50yds. to “weed out” some of the less accurate ones. Then when I have three or four types that have promise, I’ll set up and shoot them again at 100yds. to find the best.
If you are diligent, be consistent in your testing methods, and try to remove as many “variables” as possible during your testing, you will have an excellent chance of finding a brand or type of rimfire ammo that will give you excellent accuracy in your particular pistol. You might just find that you don’t have to spend $15 to $20 a box to get also! One last tip; once you’ve found the “perfect load” purchase as much of that one lot number that you can afford. Sometimes even the mid to high priced ammo will vary slightly from one lot to another. Also, when you restock, do a quick accuracy test to see if the new lot is still shooting as well as the last. If you have a year or two’s worth stockpiled of the same lot number, you can shoot with confidence that your ammo won’t be the reason if you miss a target.
Regards,
Bob

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