I recently posted of shooting my completed RKS barreled 22LR Hepburn complaining of less than satisfactory accuracy. Several suggestions were given one being to shoot at least 100 rounds to season the barrel so to speak and maybe check and or recrown the muzzle. I did this yesterday using some older Midas L ammo I had. The wax lube was a bit frosted but it was what I had on hand that wasn't standard ammo. I then shot a half box of fresh Wolf match resting at various points on the forend and barrel. I was doing 5 shot groups or attempting to. Mind you at 50 yards I would think you could expect a decent group. Half to one inch at 50 with a 500 dollar barrel? On the other hand I shot my just completed Storie Ballard with a BRC barrel and with that same old Midas ammo was getting one hole 5 shot groups of about .375 inch. I have a freshly recut and polished recessed crown on the Hepburn and after 100 rounds had a good lube "star" going at the muzzle. I have three boxes of ammo coming. Some more Midas for the Ballard and some SK for the Hepburn. That is what most of the guys at the club shoot. Going to keep trying different ammo but at around ten bucks a box I hope I can find something soon it likes. This is getting expensive...


JMH

marlinguy wrote on May 30^th, 2026 at 10:14am:

I agree.

How does it feel when you run a patch threw it? Does it feel smooth, any loose or tight spots?

I suppose it is possible to get a bad barrel, but it sure would be incredibly rare with an RKS barrel. I hear nothing but rave reviews on his barrels. That said, my last barrel was a Green Mountain extra heavy full round barrel I used on my Ballard 3F Fine Gallery restoration, and it shoots one hole 3/4" 10 shot groups at 50 yds. I never did any seasoning on it, I just shot CCI Standard Velocity in it from the start and it seemed to like that ammo. This was a summer sale barrel that cost $91 at the sale price.

With a new-to-me 22 I always run a test with every different ammo I have on hand. For example here's my test results for an old Stevens 414 for 10 shots at 50 yards with iron sights on a day with a bit of wind (rank by group size): Fed Automatch .6; CCI Pistol Match .7; Old Eley 10X .8; Wolf Match Target .9; Eley Club Xtra .9; Rem Subsonic .9 + 1 flyer; Eley Std 1.0; Fed Gold Medal Target 1.0 + 1 flyer; SK Rifle Match 1.1; Eley Match EPS 1.1; Eley Match 1.1; Eley 10X EPS 1.1; CCI Green Tag 1.1 +1 flyer; Peters Pistol Match 1.2; Win T22 1.2; Eley SilhouEX 1.25; Old Eley Std 1.3; Fiocchi Super Match 1.4; Rem Eley 1.5; Eley Biathlon 1.5; CCI STD VEL 1.6; Peters Rifle Match 1.6 + 2 flyers; Fed American Eagle 1.7; Rem 22 Target 1.7; Wolf Match Extra 1.9; PMC Match Rifle 1.9 + flyers; Lapua MSTRL 2.0; Fiocchi Match 2.1.
Later a few for 10 at 100 with scope. Fed Automatch old 1.7; Norma TAC 1.8; Fed Automatch new 2.0.
Still to be tested: Norma Match and Aguilla Super Extra.
Bottom line is that 22 rifles can be very picky about their ammo and their choices can sometimes be surprising. Also note that I have no reason to test hyper expensive ammo for non-benchrest shooting (but there might be some surprises there also). I should add that I know that the reamer used for the chamber can also make a large difference with premium barrels and ammo.

A few years ago I decided to try as many different 22s in my Ballard and 52 Winchester as I could just to see what performed the best and the results were surprising. The Ballard shot the best with CCI pistol match and the Winchester shot best with Remington sub sonic hollow points. I didn't try the high end stuff like Lapua and RKS because 3/8" at 50 yards is good enough for me. The only competition that I shoot is Sporter Rifle which is offhand at 50 feet and at that range just about anything will do that's standard velocity.

Have you tried slugging the barrel and casting the chamber yet to see if you have an overbore situation?

Ive got an italian Win92 clone with a 44mag barrel that doesn't shoot any bullet well enough. Seems the barrel was made at 5oclock on a friday before a holiday weekend, as the grove diameter slugs a girthy .435 when it should be .429. It is possible to get a poorly cut barrel. 

Also, my experience with a new 22 Bartlein replacement barrel on a Ballard No3 was holes through holes right out of the gates. No seasoning or breaking in needed. 

What reamer was used to chamber the barrel? There are a gazillion forms of .22LR chamber/throat/leade combinations out there, and knowing which one you have could save you a lot of grief and expense in finding "the right" ammo.

My BSA International MkI will group CCI SV and all other mid-grade SV ammo into an honest MOA at 100 yards. Lapua and SK Rifle Match is somewhat better. But, when I switch to Eley Tenex the groups shrink to 1/2MOA and more often than not a fair bit less (lot variations are slight and immaterial to me) - depending of course on the whims of the Wind Gods. Evidently my 76 year old BSA chamber is pretty nearly ideal for the Tenex bullet shape - a happy coincidence, or purpose on either the builder's or the ammo maker's part? Regardless, I'm happy and I don't waste my time shooting anything but Tenex in it.

Anecdotally a Ballard .22 built on a Pacific action (of all things), with a short stiff heavy barrel dotes on Tenex also and absolutely abhors Lapua Midas and Center-X, but gets by ok with SK Rifle Match.

Both the BSA and the Barrald (that's what I call it, you would too if you saw it) leave distinct but faint rifling marks on the nose of Tenex bullets withdrawn from the chamber.

Lesser rifles in my employ get fed a mishmash of decent stuff and cheap stuff, depending on the target du jour - empty beer cans and steel targets don't justify $20/box ammo, but on the other hand squirrel heads do.

I repeat, it's all about the chamber and once you decipher it a rifle's "like/dislike" of ammo becomes much less of a mystery. It's funny how a shooter can stress over bullet fit in his .32-40 and measure and calculate things every which way from next Wednesday but will in turn take a scattergun approach to .22LR bullet fit. I know I did.....

Last brick of Lapua Center X I had shot bug hole groups. One just above the 25 ring and one just below the 25 ring.

Good enough for last place in two matches. It was consistant.   

Could be an ignition problem. 

Since you used a match reamer, you’ll likely need tight headspace.  Otherwise the energy of the firing pin is wasted by having to seat round.

Additionally, you may be able to detect ignition problems by pulling bullets from known accurate ammo and firing them.  If the sound of the primed case sounds different from round to round, you might have an ignition problem.  This bypasses any headspace issues since there isn’t a bullet that needs to be pushed into the chamber.   

If you do this with cheap ammo, you might be surprised how different they will can sound. 

jhm wrote on Jun 1^st, 2026 at 3:42pm:


Not a gain twist? 

If it turns out to be a consistant twist, you could slug and measure both ends of the barrel. If the big end is at the muzzle, well...   

Or start a pulled bullet at the breech end and push it toward the muzzle. Shouldn't get loose.

I didn't want to suggest that but I was thinking that. Should be able to see if it's gain twist just by looking in both ends.  Pushing a bullet down the bore is easy.

That makes sense. When I checked the twist the patch got a little tighter about two inches from the muzzle end of the barrel. I have some SK coming to try and will start looking for some center X. Where is a good place to get ammo?



JMH

For a RKS barrel I first use JB Bore Polish paste (50 passes) to ensure all machining ridges or burrs are removed.

For a 22 chambered rifle I have noted you may need to shoot at  least 500 rounds of ammo through it before it will be broken in.

Barrels shooting high velocity jacketed bullets break in faster, however breaking in a barrel shooting low velocity plain base lead alloy bullets takes considerably more passes  to accomplish the breaking in.

I use 400 rounds of cheap ammo and then clean the barrel again with 50 passes of JB Bore Bright paste.

Then I shoot 100 rounds of my top notch ammo and do not clean it to obtain maximum accuracy.

I then only clean my 22 RKS barrel at the beginning of the season but always season it first with a hundred rounds to develop it's maximum precision capability.

Accuracy of my .22 RKS barrel after it had been properly broken in and seasoned.

I have the gain twist finishing at 16:1 with the short leade match chamber designed to shoot high quality ammo.

Ron makes the standard long leade wider chamber finishing at 17.2:1 for better precision if you intend and always wish to practice using cheap ammo.

Which barrel specifications did you order?

If you recrown the barrel you need to polish it well again with the red J-B Bore Bright polish paste.

At the other end of the spectrum, I installed a SS RKS barrel on my Stevens Walnut Hill about 2001. Popped a couple rounds off in the flower bed along the shop to make sure it went bang. Stuck it in the car and drove to Etna Green where I stuck a borrowed scope on it and shot a 243-6 at 200 yards. 6 of the rounds could be covered with a dime. The rifle still shoots that way. Stopped counting perfect scores at 12. No lapping no JB bore paste. 

Is your barrel a gain twist or a consistent twist?

Regardless if it is a standard twist or a gain twist you are NEVER EVER supposed to lap a RKS barrel.

For accuracy it has a continuous precision choke of .0004" from the chamber to the muzzle.

Lapping will result in variations or change the degree of angle of the choking or interupt the continuity of the perfect slopped choke Ron has installed. 
Doing so will reduce your accuracy by affecting the perfect precision choke he has already installed in the rifle.

It is also strongly recommended to NEVER EVER use jacketed bullets in a rifle solely intended to shoot cast bullets since copper fouling cannot be readily and completely removed and may significantly affect accuracy when you start using cast bullets (some of the time).