30 Dasher

260 Rem · #1 11-11-2016, 05:16 PM

A friend and I thinking about chambering a 30 Dasher (based on a 6 Dasher necked out to 30 cal). This should produce a 30BR on steroids. Potential for easily tunable accuracy. I am going to focus on a deer round, probably using 125 gr bullets. Anybody on the forum with 30 Dasher experience?
For reference ...
From left, 6 BR > 6 Dasher > 30 Dasher > 6.5 X 47 > 308

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Arty · #2 11-11-2016, 09:05 PM

What would you get with a 30D that you couldn't get with a .308?

260 Rem · #3 11-11-2016, 09:34 PM

The 30 Dasher will be specifically purposed to perform with light bullets (115 -125 gr) and will push them to similar speeds as the 308 with 10gr less powder. Recoil will be tamer and I expect they will be capable of very good accuracy.

3blade · #4 11-12-2016, 05:25 AM

So a 308, with lower BC/more wind drift?

Point of diminishing returns. A 308 does not have significant recoil to begin with, even in a 6 lb rifle. First shot accuracy matters, you don't get to shoot groups on a deer. Therefore the cartridge/bullet that hits closer to POA under field conditions (i.e. Wind/variable humidity&altitude) is the better deer killer.

If you wanted a low recoil/economical/long barrel life cartridge for a new hunter, who is going to shoot a few hundred rounds per year....perhaps? But it seems like a lot of work for a cartridge that will be inherently limited. Any of your 6/6.5s will have the same benefits and be better further out?

I don't claim anywhere close to your level of ballistic knowledge, but I do kill a lot of deer. Will it work? Yep. Is it better than a 308? IMO, not at all.

Altaboy · #5 11-12-2016, 06:05 AM

Sometimes it's just about the fiddling. I just built a 284 Winchester on a Winchester short action, I could have bought a 7mm-08 or a .270 or a .280, they basically all do the same thing. But then I wouldn't have learned anything and missed out on a rewarding experience.

260 Rem · #6 11-12-2016, 09:49 AM

It's all about fiddling...and 3blade is right about the 308 which has long been acknowledged here on the AO forum, as the best all-around cartridge. I have used a 30 BR for deer and can confirm it's terminal ballistics at 200m with a 110gr TTSX are effective. I expect the extra energy developed by a heavier bullet leaving the muzzle in the neighbourhood of 3100 fps, will do the job just as effectively at 300m...and maybe even to 400m in a pinch.
This year I will be using a 6 Dasher (similar ballistics to 243 Win) which will also perform with killing efficiency in my 300m "comfort" range.

260 Rem · #7 11-22-2016, 12:00 PM

The die has been cast ...and thanks to my friend that really understands this stuff, and a top notch machinist/smith ... final decisions regarding chamber dimensions are made, and my "test" barrel is in the shop. I have leaned a lot as this project is perhaps a bit more complicated than the norm. Here is what is involved.
To create the 30 Dasher chamber (without having a new reamer made), involves cutting the chamber with a 30 BR reamer, then chasing it with a 6 Dasher reamer using a 30 cal pilot. This was first done in a barrel stub and then cross sectioned to expose the fit of a dummy round. (I will get a pic of that next time I have access as it shows how things really fit in a chamber).
We plan to make a sizer die by drilling out the neck of a 6 Dasher Redding S Type bushing die to accommodate the larger 30 cal neck, and using appropriate sized bushings. Unfortunately, resizer can not be created by simply running a Dasher reamer into a 30 BR die as that part of the die is hardened too much for the standard reamer.
The seater die will be created by running the Dasher reamer into a 30 cal Wilson in-line seater blank.
My friend will have a new heavy barrel chambered. For the debut, I am simply having a sporter contour 30 BR Jury barrel rechambered.

SendIt · #8 11-22-2016, 12:19 PM

Lol i guess its a trend in this forum...you ask about a particular thing about A and the first thing that comes out is related to B...then. Barrel life blah blah blah and diminishing returns this and that.

It be interesthing to see what a 30D can bring to the table given that it for short ranges it will be an ideal candidate for slower twist barrels and bullets with lower bc since they tend to be short and stout without a boat a boat tail which is ideal when trying to minimize the effects of bullet runout which is ley player in precision.

SendIt · #9 11-22-2016, 12:21 PM

Quote:

Originally Posted by Altaboy

Sometimes it's just about the fiddling. I just built a 284 Winchester on a Winchester short action, I could have bought a 7mm-08 or a .270 or a .280, they basically all do the same thing. But then I wouldn't have learned anything and missed out on a rewarding experience.

Totally agree.... its all about that "Eureka moment"

markg · #10 11-22-2016, 01:23 PM

Sounds like a really fun project. I hope it all turns out to your satisfaction.

6.5x47 lapua · #11 11-23-2016, 01:04 PM

Why not 30x47 lapua? I would be amazed if you have any gains at all over the original but ive been wrong before.

260 Rem · #12 11-23-2016, 04:24 PM

Buddy has the 30 X 47 reamer and has built a couple that shot 135's very well. He is in on the 30 Dasher because he likes to try different things. I am in because I think it has good potential as a deer round. I have used 30 BR deer rigs shooting 110gr Barnes TTSX with 3075 fps MV ... but would like to try something in the 125/130 gr range...maybe leaving the muzzle about 3100 fps. I know the skinny barrel 30 BR's perform well and are easy to tune so I thought it would be interesting to see if Dasher version could keep up with its parent with a bit heavier bullet and a few more grains of powder. I read one account of the 30 Dasher shooting 116 grn'rs at close to 3300fps with good group results.

6.5x47 lapua · #13 11-23-2016, 04:59 PM

well here,s hoping it works for you.it is fun to do something different now and then.

260 Rem · #14 12-08-2016, 03:08 PM

Some will find this cross section interesting as it shows how things fit in the chamber. Now have all the goodies to make the FL resizer and seater dies. There will be one change in the chamber cut, that being to reduce the void length that you can see forward of the case mouth in the pic. This dimension will be reduced to accomodate about a ten thou growth over the established trim length.

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260 Rem · #15 04-04-2017, 02:09 PM

Bump for Update

260 Rem · #16 04-04-2017, 02:24 PM

A brag group from today ... the best I've shot with the 30 Dasher to date.. Five shots into 0.204 at 100m is sweet from a barrel with a 0.70 MD...not likely to happen again soon. Thought I'd try a Benchmark barrel. Gained only about 100FPS over the 30BR for accuracy load although an increase of 150FPS is no problem but the groups open to 1/2". These are Ber 115 FB leaving the muzzle at 3050fps.

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gitrdun · #17 04-04-2017, 06:58 PM

Question for you 260rem. If the 30 Dasher is based on a 6 Dasher, which is based upon the 6 BR, does the 30 Dasher also incorporate the smaller flash hole which the 6 BR is known for? The reason that I ask is that I had to be careful with my universal de-capping die with the 6BR and grind it down a bit as to not stretch the flash hole.

260 Rem · #18 04-04-2017, 07:51 PM

Yes ...standard small flash hole....The 30 Dasher is simply a 6BR...with shoulder blown forward to create the 6 Dasher...then necked up to 30 cal. My 30 Dasher resize die is a Redding 6 Dasher die with the neck opened to 30 cal.

260 Rem · #19 10-14-2017, 02:56 PM

Bump for update

260 Rem · #20 10-14-2017, 03:17 PM

I had a second barrel chambered to 30 Dasher ... actually was a 30 BR that had been shot some ... a Jury sporter contour with a 0.63 muzzle diameter. Just started shooting it with good scope and like its parent, was easy to tune. Looks like good consistency with 34.8 gr which is only 1 gr above the parent case. Hopefully there is another node a bit higher because it only gained 30fps ... oh well, nothing ventured, nothing gained.