Alycidon

Tighter the neck the longer the case life, less expansion so less likely to split. Friend of mine, a retired master riflesmith who spent his life working on barrels and actions for double rifles for the best London houses introduced me to fitted necks when he built my 20BR. His short range fox rifle was a 22.250 he built himself when the caliber was a wildcat, used the CFT action that he designed for BSA. Using fitted necks he was getting 80 reloads per case, the only time they needed binning was through flame erosion. Most reloading 22.250 cases today will struggle to get 10 loads per case, he was getting 80 + in the 1960s. Fitted necks need several extra steps in the reload procedure, this is a whole different ball game, the tools and bespoke neck bushes are built specially. My 6PPC runs `1.4 thou of clearance using lapua brass, pretty standard reloading dies/bushing etc, works fine. Personally if it shoots well then I would leave yours alone. A

I have 20BR, and had a friend with a 22BR until he left the field a few months ago, both full custom jobs. . As OSOK says you will need to go a long way to beat them, and he has had vastly more experience with these calibers than most people here and has the awards to prove it. When I was looking at having my 20BR built some 15 years ago I went to OSOK for advice as I knew he had one, his was probably the first in the UK, I think mine was the third, certainly it was the first one the Birmingham proof house had seen.. I took mine to Bisley on 100 yard benchrest, always came top 3 except once when two of the England squad were shooting, and always against dedicated 6PPC bench guns. turret rests etc. I was using a short Harris bipod and a rear bag. Only downside is single shot only but I killed three large cubs in 30 seconds easily enough one night with my 6PPC. 95% of the time you only get one bang at a fox, then you spend the next 2 years trying to get another one at the same missed fox. If you want to shoot where a .2 group or less is required and a .4 is nowhere then that is what you need, however if its a fox flattener then that level of accuracy is not needed and 204 or 20 Prac/20 Tac will be fine out to 300 yards with 39 SBKs. Much over that then heavy 50 or 55 grain Bergers in a 1 in 9 twist are in my book the way to go from an accuracy perspective, they are significantly more efficient, less drift, less drop than anything similar including 22.250 with 50s. But 98% of shots should be sub 300 yards so its very subjective. A

I my experience the 20 cal 39gr SBK and a 55 gr NBT ( in a 22.250) will both go straight through unless its a front on bib shot. Killed 2 foxes one evening with a 39 SBK, by accident admittedly. Through the front ones boiler room sideways on just as another one ran past the back of it, through that ones neck as well both instant kills. A

204 will drop less and drift less than 223 but sub 300 yards there is very little difference. Personally I very rarely shoot at 300. I found that my 22.250 tended to hit harder than my 20BR, but dead is dead, just less spatter. A

20BR, had it over 10 years so way before 204 appeared, great caliber, usually use 39 SBKs or 50gr Bergers. Download mine to around 3500 using N150 and BR4 or Fed 205 primers, over 14lbs so very smooth to fire although if I am likely to have to carry it far then I take something else. You mentioned a shorter barrel, you will loose about 30fps per inch of barrel, so a 22 inch given the same load will be around 150 fps slower than a 27 inch, nothing you hit in the boiler room will complain about the lower velocity though. A

Use VIP on game, but only about 400 a year. No issues at all. A

N550 is in fact slower than N150, I know that Vit suggest otherwise but thats what I found when I tried it and N160 as well., you should ideally fill up to the base of the neck or close to for a nice even velocity spread. To do that may mean using a slower powder than is generally advised but it pays you back with single figure ES sometimes and rarely more than a 20 fps difference in a 5 shot string. Its not the drops that get you at long range, you can range and dial that out but its the drifts as I am sure you are aware, thats why I went for the Berger 50 as at the time it was the heaviest 20 cal bullet out there. But in practise 200 yards is a pretty long night shot for me, so drop/drift is academic. Zero 1 inch high at 100 yards, puts it on at about 180, so its 200 yards plus before you have to think about anything if its a chest shot, I appreciate that you dont get time to range at night usually but if you shoot at a constant mag ( I usually use 8x) then you know how far a, by the ground assuming you know your ground and b, by how it fills the reticule. Building a high speed 20 today I would build it around the 39 SBK and 1 in 11., ( think thats what Sierra advise) . Re charges, around 32gr/33gr from memory, it was some years ago now, my working load is around 29.5 gr, (3500) to give me a consistent ballistic curve and similar velocity I deduct .5gr when loading for the 39gr. Had that rifle for around 10 years, only ever missed 3 foxes with it ( all were perfectly straight forward 150/200 yard shots) but my declining eyesight ( I am 66 now) means it does not now get the night use that it used to some years ago. Been out to 300 yards on foxes with the 39s with no issues but on a front on bib shot it does not usually exit. Have you had a look on Quickload to see if 38 gr of N550 can be burnt in a 26 inch tube ?, might be an idea if not, extra barrel length = extra time in barrel = extra velocity, around 30 fps per inch. No point loading 38gr if the barrel is not long enough to burn it all. You might also check that it will fit your cabinate, thats something I forgot, luckily it JUST went in. The only drawback with a long tube it that its a pain to handle inside a 4x4 and forget carrying it very far unless you are young and fit. In my experience you dont get a second shot at anything you have missed, its dead or its gone, ( I missed more than a few in my 22.250 days !! ) I suppose a quick reload is handy if you mess up the placement, knowing you only have one pop does make you wait till everything is about perfect, so no Chinese heart shots and no going out in high winds. I have only ever had one occasion where a fast follow up would have been handy and that was on my 17AH ( which is my least favorite fox round). I have had the ejector removed on all my rifles except a semi 22LR, as I dont want to lose expensive Lapua brass that has had a lot of prep work, yet one night I killed 3 foxes ( almost full grown cubs) and had a miss all in around 30 seconds including working the lamp and having to move the Disco slightly for the last one, I have a butt stock shell holder to keep fresh rounds handy. My action is Lawton 7500 single shot, one of the first in the UK, (Lawton failed as a business when the owner Barney Lawton died, ) a single shot actions supposedly flexes less under firing and are therefore a shade more accurate ( supposedly) than a magazine fed action , if you shoot 100BR a .1 increase in group size can be the difference between top three and nowhere, but for a sporting rifle then it would be perfectly good, horses for courses. Have a look at Saubier for more info on 20-250 if needed, I have no experience of it but do have hands on experience of 22.250 and 22.250 AI, both sad stories. The AI belongs to a friend who also posts here occasionally, having shot out the barrel trying to make it shoot it was re barrelled to 22BR and it now shoots .2 - .3 from the off with minimal load development again a single shot action, Hope you have more joy with the .250 case than we had. A

28 inch Bartlein, 1 in 9, so hardly ideal, 1 in 11 would have been better but the rifle was built around the 50gr Berger. I went to around 4100 with the 39, no need to go any faster, but was getting pressure signs at that. Have also been to about 3900 with the 50 Berger, match and varmint, they also held together fine. I would suggest as a working load 3300/3600 will be where you will find best accuracy, given a heavy rifle ( mine is 14lb) and no mod you should be able to see the bullets arrival. I shot a crow with it some weeks ago at about 160 yards, it dropped off the top of a drinking trough before I had registered the gun had fired. If you are going 20BR then I would advise using N150 and either BR4s and Fed 205s, that gives you a nice case full so a close velocity spread. Dont forget barrel life is around 1500 rounds at sensible pressure and velocity, you start pushing the limits and this will drop down to around 600 rounds, thats a pound a round plus just for barrel life. You will find it beneficial to weigh and batch your bullets by weight, use your powder scale. Bergers are pretty good, I once had 200 x 50s, ALL were 50.0 or 50.1 which is remarkable. I usually find in SBKs a spread of plus or minus 1 grain with the bulk falling into two or three weights. For a pest control bullet thats perfectly acceptable. A

Run with the N135, that will be fine. A

Data on 223 and N120 is available free here: https://www.vihtavuori.com/reloading-data/rifle-reloading/?cartridge=7 Personally I would have said N120 is a bit fast for the caliber but you should be able to get away with in on the 40 gr VMax, For the 50s etc I would deffo look for something slower like N133. Ideally you want a pretty full case, (95% or so), that way you get a uniform velocity, so a closer shot to shot velocity and thus a smaller group with less vertical dispersion. I would also recommend a look at Sierra Blitzking, I use the 20 caliber 39s in a 20BR and 1 in 9, hell of a good bullet, holds together at over 4000 unlike the 40gr VMax. But best accuracy as is often the case is way below top speed, in my case about 3600. A

Superb pic, well done. A

Try N150 then, or N550, I found that 150 was faster than 550, this is not what the books suggest. ( 20BR) , My advice is load for accuracy not speed, nothing hit in the boiler room at 3000 or 4000 will not tell the difference. A

It just shoots very sweetly at 3500, .2 off a bench when I do my bit, no mod yet see the impact, ( its a heavy old set up), in my 100BR days it used to agg high 2s or low 3s off a bipod with a rear bag, no pedestal rest. Start getting it up to around 3800 with Berger 50s and I get pressure signs on the primers, I have taken 39 gr SBKs over 4000 yes but increased recoil ( and faster barrel life) means I dont see the impact. Very rare I go much over 200 ( my old eyes are not getting any better) but have taken them comfortably off the Landrover wing mirror at 300. All my other rifles are set up at around 3500 so it makes the trajectory curve that much easier to master if a snap shot is needed. Yes a 22 will make a bigger hole, I had some spectacular splatter kills with 55gr NBTs through a 22.250 on things like rabbits but dead is dead, bang flop with both every time. Both Berger 50s and 39SBKs usually pass through, front on fox at 300 the 39s dont usually. Interestingly a friend shot a fox with a 257AI some years ago and could not find it. I went to pick it up next morning, about 100 yards further on that he thought, front on chest shot, no sign of an exit, small smear of blood on entry, but chest was twice the size it should be. I was expecting to need a shovel !!. A

Under 300 yards there is little to choose between 204 and 223, I use a 20BR downloaded to around 204 levels, over 300 yards wind drift is usually less than the same weight of bullet in 223 but 223 is able to fire much heavier bullets if needed. Horses for courses. A

Why is mag feed so critical, you miss and its gone, no chance of a second go. I use single shot rifles with ejectors removed as I dont want to loose hand formed brass. I had killed 3 foxes in 30 seconds and has a miss as well. Bloody things came piling out of a wood one night. No real experience of the bigger case 22 but a friend has a 22BR on a single shot action and get on well with it. I use a 20BR and again no issues with rate of fire. A