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April 3rd, 2012
GS Arizona, a top small-bore and centerfire shooter, uses the 6XC cartridge in some long-range matches. He has tried a variety of different types of brass for this cartridge, including necked-up 22-250 brass and Norma 6XC brass from David Tubb’s (Superior Shooting Systems). German’s measurements reveal significant differences in water capacity, as well as neck-wall thickness.
6XC Source Brass Dimensions
Case Capacity and Pressure Issues
GS has noted significant variances in capacity among the different “flavors” of brass. Norma-headstamp 6XC brass has 49.3 grains of H20 capacity, while Norma 22-250 brass holds only 47.8 grains of H20. Third-generation Tubb-brand 6XC brass is somewhere in the middle, with 48.6 grains of capacity. The tester did not have a chance to measure the high-quality Lapua 22-250 brass introduced in 2010. NOTE: These differences in case capacity are large enough that you MUST adjust your load to the brass type.
 We ran a 6XC QuickLOAD simulation with 115gr bullets and H4350 powder. QuickLOAD predicted that the observed difference in case capacity can result in pressure differentials as much as 4,500 psi! In other words, if you switch from Norma 6XC brass to a lesser-capacity brass type, your pressures could rise 4,500 psi (using H4350 and 115gr bullets).
We recommend sticking with the Norma 6XC brass. It is available from DavidTubb.com for a reasonable $69.00 per 100 cases. These days, that’s cheaper than many other types of premium imported cartridge brass.
Neck Thickness and Chambering Issues
German noted that the different types of available brass varied quite a bit in neck-wall thickness — from 0.0121″ (Norma 22-250) to 0.0140″ (Tubb 3rd Gen). Consequently the diameter of loaded rounds also varied. Depending on the brass you chose, your loaded rounds could be 0.267″ at the neck or 0.271″ (with no-turn brass). That’s a huge difference and it’s something you need to take into account when you have your chamber cut for a barrel. For a cross-the-course rifle, you might want a chamber with at least .003″ total clearance over a loaded round. Obviously, to achieve that clearance, you’ll need to set chamber dimensions base on your preferred type of brass.
NOTE: The research for this story was conducted in 2010. Dimensions may have changed with more recent production, so you should double-check the case capacity of your own 22-250 or 6XC brass.
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July 1st, 2010
Lapua’s new 22-250 brass has finally started to arrive on dealers’ shelves. Forum member William P. (aka “Heath”) just got two boxes of the new brass. Both boxes have the same lot number. Heath was kind enough to sort the brass and report his findings.
 
Based on Heath’s 200-count sample, we can say this new brass is very, very consistent in weight. The total weight spread (delta) for 200 cases was just 1.4 grains! And the vast majority, 83%, were within 0.7 grains in weight (160.3 – 161.0). For the varminter, sorting may be superfluous. Once again, Lapua has produced a superb new product, and we love the new, blue plastic boxes.
FYI, you 6mm shooters should know that the Lapua 22-250 brass can be made into quality 6XC brass. And it’s even easier to create a 6-250 wildcat. In May, Robert Whitley explained how he created a tack-driving 6-250 Wildcat from the new Lapua 22-250 brass.
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May 1st, 2010
Our friend Robert Whitley of 6mmAR.com has come up with a new, accurate 6mm wildcat based on the new Lapua 22-250 brass that has just started arriving. Robert provides this report:
“I just received a box of the new Lapua 22/250 cases — beautiful brass! My real desire with it was to make it into a 6mm version, preferably something that was ‘no neck-turn’ with a .308 Win-type body taper that would work well in bolt gun and semi-auto magazines and would have a capacity to allow superior velocities. I considered the 6XC, but since you have to bring a whole lot of the shoulder of the brass up into the neck (when you re-form the brass from 22-250 to 6XC) that would necessitate neck-turning it because with Lapua brass the shoulder metal is thicker than neck metal of the brass.
I wanted a simple ‘neck it up and shoot it’ approach so I made up a 6mm-250 Improved 30 cartridge (i.e. 6mm-250 Improved with a 30 degree shoulder) and this thing works great — just neck up the brass, load it and shoot it! The case is like a 6XC with a .030″ longer body and a .030″ shorter neck, which works out fine if you are going to be shooting mainly the 105-108 gr bullets (which it will do very well shooting 2950 – 3000 fps). If you want to hot-rod things, which I do not, I am certain the case can push the 105-108 gr bullets a fair amount faster.
I set it up and throated the reamer for the Sierra 107s and the Berger or JLK 105 VLDs (i.e. a .090″ free bore on the reamer) and it works great with them. If I was going to use it with the Lapua 105s or the Berger 108s I would add about .025″ – .030″ to the freebore of the reamer (i.e. make the freebore around .115″ to .120″).
The great thing is you can use a 6XC die set for it without modification, and all you need to do is keep the dies about .030″ up off the shell holder from their normal position and use them as is. You can make a spacer washer about .030″ thick that you can put on and take off the 6XC dies and use the dies for both cartridges (i.e. 6XC and 6mm-250 Imp 30).
 6mm-250 Imp 30 Shows Great Accuracy
Fire-forming loads are real accurate. Here is a 10-shot group I shot prone at 100 yards shooting fire-forming loads with it — the group is the size of a dime. For fire-forming I use a milder, but still very accurate load: 32.0 grains of N140 with a Sierra 107 and a BR2 primer. For fire-formed cases you can jump up to N160 (around 38-40 grains — depending on lot) and it will push the 105-108 gr bullets real accurately in the 2950-3000 fps range, with low ES and SD. This cartridge has a neck length of .268″ which is plenty long for a 6mm shooting bullets with varying bearing surface lengths. The reamer diagram (link below) leaves about a .003″ neck clearance over a loaded round, which seems to work out very well for a ‘no-turn neck’ set-up.
So there you have it … the 6mm-250 Imp 30 is simple, easy to make, accurate as all get out, there are available factory die sets you can use, and it uses great new Lapua brass — what’s not to like!”
CLICK HERE to download Whitley 6mm-250 Imp 30 Reamer Print.
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January 27th, 2010
Howa previewed some impressive new varmint models at SHOT Show 2010. We liked the new Howa 1500 Thumbhole. This features a skeletonized, laminate varmint stock with a nice wide, flat fore-arm. The fore-arm is about 2.25″ wide and is completely flat on the bottom. Slab sides run almost all the way back to the action. This provides a very stable platform that should track well in the bags. Varminters put lots of rounds down-range, so barrel heat can be an issue. To help keep your barrel cool, the fore-arm has four “Buick” vents on each side (left and right), plus SIX large vents cut in the bottom.
Behind the action there is a comfortable pistol grip carved at a good angle for shooting from the bench. It has a nice palm swell at the bottom but is narrow enough at the top that you can get your thumb around for secure, properly aligned grip. I tried out this stock and it was very comfortable. The slightly raised comb was shaped nicely and the grip really felt good in the hand. The middle section of the stock is completely carved away (presumably to save weight). However on the last 5″ or so, the stock has a conventional section on the bottom. This provides a solid platform to ride the bags.
The new Howa 1500 Thumbhole Varminter will cost between $695 and $830 depending on chambering. It will be offered in both short action and long action versions. Available chamberings are: 204 Ruger, 223 Rem, 22-250, 243 Win, 6.5×55, 25-06, 270 Win, 308 Win, 30-06, 300 Win Mag, 7mm Rem Mag, and 338 Win Mag. For more information, contact Legacy Sports Int’l, USA Distributor for Howa rifles.
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December 5th, 2009
 We have confirmed that Lapua will produce and distribute 22-250 cartridge brass starting in early 2010. The official product release will be at SHOT Show in Las Vegas (Jan. 19-22). We don’t have production samples yet, but there are about 1000 pieces of brass in the hands of testers in the United States at this time. This stuff is for real — CLICK THIS LINK for PHOTOS.
 One of the folks lucky enough to get his hands on the new Lapua 22-250 brass is writer/shooter Steven Boelter, author of the Rifleman’s Guide to Rimfire Ammunition. Steven has measured and inspected the new brass and he says it appears to be “on a par, quality-wise, with Lapua’s 220 Russian and 6BR brass”, which is saying a lot. Steve adds that: “[what I have] is in fact part of a pre-production run, and the main stuff will be ready for second quarter, 2010″. Steven is working on an article for Precision Shooting magazine that will include exact dimensions for the new brass, as well as initial load testing results. An exact release date for Steven’s article has not yet been set, but Boelter hopes the story will come out in January or February.
Boelter can’t say much more about the brass prior to publication of the article. But we can confirm that it has a large primer pocket, standard 22-250 rim size, and it is annealed like other premium Lapua brass. Steven has posted a couple photos of the brass on the Saubier.com web site.
We’re always excited when Lapua decides to expand its line of cartridge brass. For 22-250 shooters, who will now have a new ultra-high-quality brass option, the news of Lapua 22-250 brass must be like an early Christmas present.
Link to Lapua 22-250 Brass Photo
Above is a QuickDESIGN diagram of the 22-250 Remington cartridge based on CIP Metrics converted to English units. This is NOT the official print for the new Lapua 22-250 brass, which may vary slightly in dimensions. We suggest you get the actual production brass in hand before ordering new chamber reamers or dies.
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