6mm/.22-250 versus 6BR

[steveN]

New poster here and looking for answer to question I posted over on main message board. Would like opinions on ballistic and inherent accuracy differences between these two cartridges. Want to build 6mm bore dual purpose rifle for varmints/casual target use to be built on a repeater bolt action. After research I have learned there are reliability issues with feeding the 6BR through a magazine due to the short fat case design. Can 6mm/.22-250 be a viable alternative to 6BR in equally well built high quality target grade rifles? Realistic maximum range would be around 800 yards. I am striving for efficiency and relatively long barrel life and am not interested in high capacity cartridges such as 6/.284, .243AI, etc. Bullets used would be in the 85-107 grain range through a 28" barrel of appropriate fast twist. Thanks for any info or thouhts, pro or con.

 

[Forum Boss]

Want to build 6mm bore dual purpose rifle for varmints/casual target use to be built on a repeater bolt action. After research I have learned there are reliability issues with feeding the 6BR through a magazine due to the short fat case design. Can 6mm/.22-250 be a viable alternative to 6BR in equally well built high quality target grade rifles? Realistic maximum range would be around 800 yards. I am striving for efficiency and relatively long barrel life and am not interested in high capacity cartridges such as 6/.284, .243AI, etc. Bullets used would be in the 85-107 grain range through a 28" barrel of appropriate fast twist. Thanks for any info or thouhts, pro or con.

Steve, maybe everyone was waiting for David Tubb to tell you about the 6XC. Anyway, first off, the 6BR will do exactly what you want your gun to do, exceptionally well. At the Hickory Groundhog shoot, the "top money" varmint shoot in the country, last year 6BRs or 6 Improveds took 6 of the top 10 spots, with a 6PPC making it 7 out of 10 for 6mm. The winner used a 6 BR, and set a new record. So the accuracy will be there. Loads are well known, and the brass is the best you can buy. A 28" barrel is a good choice if you want to shoot the 105-107gr bullets.

The 6BR burns less powder than a 6-22/250 and should give you longer barrel life with better accuracy. That said, the 6XC is a "next-generation" 6-22/250 with a 30-degree shoulder, very strong web, and accuracy is obviously excellent, as shown by David Tubb's results. The third generation of 6XC brass is slated for release in mid-February.

Here's our call. If you want max velocity, and mag-feeding is really important to you, we would go 6XC, or do a 6mm-22/250 using the Norma 22/250 brass if you can find it. Or, build a 6x47 Swiss Match using the once-fired RUAG brass from Neil Johnson. But Tubb has the whole package worked out--brass, dies, loads.

If your primary concern is accuracy and you will be shooting the 80-90gr bullets, we would definitely go 6BR, with a .271 or .272 neck. You'll have an edge in accuracy, plus better brass uniformity, longer barrel life, and less recoil. If you will be doing a lot of groundhog and prairie dog work, you might look into the 22BR version. It is a very simple wildcat to make and it shoots really well. See: http://www.6mmbr.com/22BR.html

As to mag-feeding from a 6BR, the 6XC has the edge, but, for Rem actions at least, there is a good solution that works for many folks. See this article by Mike Bryant: http://www.6mmbr.com/Rem700magfix.html

Here's a pic of the completed conversion:

 

[steveN]

Thank you for the informative post. I have read about and researched the Tubb 6XC and like the concept, but my thoughts were for using the standard .22-250 Rem. with no other changes, other than necking up to 6mm. Ultimate velocity is not my highest concern as I prefer to favor consistent accuracy over highest speed,milder powder loading than max) but having extra case capacity for the heavier end of the 6mm bullets would be a nice "extra" for shooting longer range. I know brass quality is very consistent for 6 BR with Lapua cases and might be hard to match with .22-250, but regardless of the cartridge I choose, cases will receive full match prep. The link for the magazine mod was very informative. Thanks again.

 

[mikeinct]

Steve I recently put together a 6mmbr in a rem 700 action [no magazine] I like the accuracy very much so far the best group was under an inch at 300meters..The only complaint I have is I used to just shoot my old 22-250 with 55gr bullets at groundhogs..Nothing short of pure poison there instant death..I had a couple of big groundhogs flop around some after taking a solid chest hit using the 6mm 87gr V-max bullet & almost 31grains of varget in my Br gun..Before finding this site I was going to build the 6mm X 22-250...Actual case capacity is larger & should get u that extra couple of hundred FPS..the quality of the remington [or god forbid winchester]brass is suspect..If u can sort or get them uniform enough I think u will be ok in the accuracy dept..It will be some effort compared to the Lapua brass for the BR guns...Still I'm thinking it may be worth the effort..My gun has a one in ten twist so I use the 87 gr bullets I've tried the 75gr v max & it did not shoot one hole groups at 100 yds..I thought the 75gr would be a more explosive loading..not sure because I only have used the 87gr on groundhogs..the 75gr loads never got past paper testing...I don't think u will realize a full ten percent increase in velocity 6mmbr vs the 6mm 22-250..but others here with way more experience may say go for it..Even if u only get a modest increase in velocity but more explosive effect I think it may be worth it..one thing is for certain u will need to really pay attention to the finer points of reloading quality ammo..once u use that lapua brass there is really no going back to the factory american brass...Keep us informed about this project..I'm trying to talk my buddy into letting me put that caliber barrel on a short action savage I'm building for him in 6.5 X 284...Too many calibers & not enough time to play with them all...good luck, mike in ct

 

[Forum Boss]

Mike,

Try the Berger 80s in your 6BR. You should be able to drive them faster than the 87 V-Max, and for me at least, they proved WAY more accurate than the 75gr V-Max. I was using pretty much a case-filling load of N135. Berger makes the 80 with both a big hollowpoint and a conventional small hollowpoint. The big HP version shot great for me, but the other version has a better BC.

 

[jb747]

My wife has been shooting a 6mm 22/250 for the past few years. We're just starting the planning to build her a new one. It's been an excellent round. Her shooting is mostly rabbits out to about 400 metres, in a pretty windy area. Occasionally she shoots at the range. Most of her brass has been prepped Winchester, but I'll make up the next batch on Norma 22/250. Shoots the 70 gr Blitzking at about 3450 fps to great effect.

Rifle is a Rem 700, that was originally chambered in 243. The 6/250 rounds fed perfectly from the magazine. Later changed to a HS Precision mag, and feed is still perfect. New rifle will stick with the Rem BDL mag.

 

[Wild_Bill]

Why not wait for the new Lapua 6.5x47 case it is 40 thou shorter than a 22-250 case and just a slightly smaler capacity when both cases are necked to 6mm it should be an awsome performer and should also feed perfectly from a magazine they should be available verry soon. There is a guy here in Australia using a straight 6mm-250 no changes but necking it up to 6mm and Norma brass he is using it back to 1000 yards with 107gr bullets and results are verry promising.

Cheers Bill
Australia