The 6mm/06

Retrieved: 08/22/2016
Last Post: 01/26/2015

Hey fellas, one of my boys just had his 6mm/06 finished. He did it in a T/C Pro Hunter 28" tube. We are working up loads for it. I was hoping one of you guys could give me some help. 85 and 100gr pills with IMR 7828SSC and maybe WC872. I know the 872 is very slow and velocity will suffer (I think). This cartridge is capable of 3500 easy with the 85gr pills (Right)?

carpooler
11-17-2014

You might have your son look at the Hornady 80 gr. GMX's. They are as long as some 100 gr. lead cored spitzers, and will jump this cartridge into a higher level of killing power. But if I want real bullet "petals", I will stick to the lighter TTSX's from Barnes, in my 270 Win. You can get a good look at substituting these homogenous bullets for 100 gr. lead cored ones in the new Nosler Load Data, online page, for the 240 Weatherby. Both IMR 7828 and Reloader 22 seem to like to run at near 100% loading densities, in the loads published here. Most of the other powders, and with the lighter 85 gr. bullets, are grouping their accurate loads around 85%+, loading densities.

carpooler
12-14-2014

6mm bullets, like Pinocchio's nose, just seem to keep growing longer, these days. At some point the 243 win. will make more sense in a short action like a Model Seven. In your longer Mauser, its a non starter, between these two.

But I disliked my two 284 Win. based rifles, because their rebated rims kept pulling off in my file trim, forming dies. I never lost one in either rifle, but only in these dies. If the brass supply will finally ease up, I think that the new 300 RCM's will solve things nicely. I squeeze them out to 54mm, and they do not pull off any rims, period. The 284 is 55mm, and the 6mm Remington is 57mm, so I only have 3mm over the 51mm. 243 Win.

I will admit that as of right now, in a short action, the 6mm Remington has the longest neck. I will need to make up some cases 56mm long to really get a better neck, than in all of these above examples.

spitfire_er
01-12-2015

Try Ramshot Magnum if it is available. I'm shooting a custom 6-06 Improved wildcat with 56-57 gr and 105 A-max with 215M primers.

3,800 fps with a 105 out of any 6mm-06 is basically impossible. I'm running the above load at 3,250fps and I could push it up another 100 fps but it is pushing it out of a 26" barrel. You are not going to get much more out of a longer barrel either.

4831SC is a good powder to use too!

carpooler
01-15-2015

There are a couple of constants here. You have to use a powder which really flows smoothly into this case. The biggest danger is a case like this only half to 3/4'rs full of one of these slow burning powders. IMR powder kernels are getting to where they might bridge over. And to stay on the safe side, I'd suggest a powder which seems to like 95% + loading densities. This will give you a little added leeway in cutting your starting charges. The Nosler load data online page, gives you most of this, in their 240 Wea. listings. I drove 30+ miles out of town to score a couple of these 1 lb. cans of powder. I'm dedicating these purchases for my 243 VampKat wildcat, which is about 5.5 grains larger than the 240 Weatherby.

If a dealer only gets a small fraction of his propellant order, then the hazmat fee, akes a bigger bite out of each one lb. can. I found that this pushed the price of a 1 lb can of Reloader 22, up near $35 with the Wash. State Sales Tax.

okie44
01-26-2015

I put the reamer to the 243 Encore, made a dummy round to check the throat. I might need to open the throat a little bit. Will see, range time soon!

carpooler
01-26-2015

Okie 44, would you please put up a measurement of how much neck length, and neck wall thickness, this 24 x 06 case of yours, still retains from its parent case? I've just formed down a 300 x 375 Mildcat case, I received from another poster here, and now I have way too thick of neck walls at 7mm. Going down farther, to the 6mm will make this even worse.

Using 300 RCM parent brass was the better way, for me to go, but it left my necks as short as a 243 Winchester's. Forming down some 350 Rem. Mag. belted brass gives a slightly better neck, but these have to bulge out ahead of their belts, which isn't a good reloading practice.

If neck lengths are really important to you, then making a 6mm x 350 Rem. Mag. wildcat has some sparkle to it. Because these only head space on their belts, a G.S. can order a reamer which pushes back the shoulder, to make the desired length neck, and still have the nominal 6 x 284, or 6 x 06 capacity.

As one might surmise, making brass for a 6mm x 350 Rem. Mag. out of 7mm Rem. Mag. parent cases, will run into the same thick necks as I am experiencing right now.

It seems to me that if your necks are also on the short side, the only "free lunch" will be to buy a forming die set and form all the way down from the cylindrical 30-06 basic brass, if you can even find it. I found that I gained about 3/16th's of an inch in C.O.L., by forming my own full length Ruger wildcats from the 375 Ruger cylindrical Basic's brass. My G.S. has his own set of neck throat reamers, so lengthening a wildcat chamber's neck and throat is both quick and simple.

At least by making cases up to shoot out of an Encore, you won't have any magazine length issues to worry about. My present 243 Wildcat has 5.5 grains of H2O more capacity than does the 240 Weatherby. So that's why I'm searching out ways to make slightly longer necks, regardless of the case forming difficulties.

The Hornady 80 gr. GMX is as long as the Remington 100gr. PtSP's, but you can still use full loads, published for 80 gr. lead cored bullets. So gearing up to use these for hunting, exacerbates throat erosion, even more.

And yes, using a Hornady 80 gr. GMX with a 26 inch long barrel, will get you close to 3800 fps. My test bed 243 x 300 RCM is in a Mauser M-98, so I can seat my bullets out as far as I care to, just like in your Encore. Time in flight; "Oh Lordy, what time in flight"?

I'm not criticizing your project at all. I am shooting mine in a shot out Shilen take off target barrel, from a Mark X, with a 1 in 14 twist. Its original chambering was the Rem6mmBR, made for 200 yard matches.

I have a left hand donor rifle in 300 RCM waiting for a new fluted Hart barrel, and I want to get my ducks, all in a row, before spending that kind of money. My G.S. has ordered so many of these, that he's now getting their volume discounted prices.