Anyone own a 7mm 300 Win Mag?

[Weaselthis]

Jeff:
Now THAT is something I would pay good money for! If you decide you wanna do this, I'm in! I have ZERO skills w/ a lathe. I can barely operate a chain saw! I'll pay ya!

I just bought 150 pcs. of Nosler brass in 300WM. I really like it in my .280AI. But, I am going to buy some cheaper stuff to practice on before I take the plunge w/ this $1.30 each stuff!

Can you tell me what size bushings you now use to get from .308-.284?
Do you use the Titanium ones?
IF the number of bushings/cost is equal or greater than the cost of a custom die, would it not make sense to just get the custom? CAN one get a custom die from Redding?

Thanks! ahh......the anticipation builds!

In my opinion the Redding "S" type competition neck bushing die is the only way to go. Then have a 300 win body die if you need to slightly set the shoulder back a bit. The problem with using the bushing neck die to neck the brass from 300 to 7mm is, the redding bushings have only a very slight taper on the bottom and are designed to accept brass that is only slightly larger. So you need to do it with several bushings and small steps. I have always wanted to take a 7mm bushing to a lathe and cut a larger dia slow taper on one side. I think that would do the trick for first time sizing down. Then flip the bushing over or use a second bushing for the final size after fireforming. I have pretty much completely converted to the Redding comp bushing dies. I like to size my necks and body in seperate steps as the body seldom needs sized. I get concentricity of less that .001" T.I.R. as an average and I like that.

Jeff gun)gun)

 

[tresmon]

Thanks for the info.

So I think I read in this thread that the 7-300 is good for an additional 150fps over the 7mmRM. ?

What is barrel life like? What kind of round count could a look for in a match rifle?


And are you guys saying you neck only size your belted cases? I have had EVERYONE tell me to always FL size belted cases..... Sierra Bullet techs, Sinclair International techs, etc.


Thanks.
Tres

 

[Weaselthis]

Tres, I'm sure there are MANY people on this forum much more knowledgeable than I, but I can give you MY experience w/ a 7RM.

I never, in over 2000 rounds thru my old gun FL size until I could no longer close the bolt without a LOT of difficulty. This, being a hunting rifle as well. If I didn't have to struggle a lot with closing the bolt, I continued to neck only until I did. (fyi, i ran EVERY round thru the mag/chamber BEFORE a hunting trip to weed out those that needed FL sizing).

The number of reloads varied, but I couldn't tell you EXACTLY how many, because back then, I didn't keep real good records of how many time a brass was fired. My sense was that it was at least 5-6 times. Of course that would depend on a lot of things like how hot ya run it, etc. and I trimmed regularly.

When it got too hard to close the bolt, I FL sized 'em & kept on shooting. I shot out the first 2.5" of my bbl. and THAT'S what prompted this new 7mm/300WM build on a 7RM take off bbl. I bought.

Good luck.
btw....thanks again for all the great reloading info on your write ups. I'm learning a LOT from all you guys on this board!

Thanks for the info.

So I think I read in this thread that the 7-300 is good for an additional 150fps over the 7mmRM. ?

What is barrel life like? What kind of round count could a look for in a match rifle?


And are you guys saying you neck only size your belted cases? I have had EVERYONE tell me to always FL size belted cases..... Sierra Bullet techs, Sinclair International techs, etc.


Thanks.
Tres

 

[tresmon]

What's barrel life working out to be on this one??

 

[Broz]

What's barrel life working out to be on this one??

Tres, I can't tell you when this barrel will start going away. But I can tell you that we have around 700 through it by now I would guess , and it still shoots very well. Also we have never rapid fired it, we try to keep loads below max and most groups we shoot are 3~4 shots.

Jeff

 

[tresmon]

So what load data you use???

Thanks,
Tres

 

[statjunk]

I also add that I've shot the 300 WM for a long time exclusively neck sizing and I've never had a problem.

Tom

 

[Broz]

So what load data you use???

Thanks,
Tres

It was a Hybrid... I used what I knew from a 300 win with a 180 weight bullet. started low and worked up with H-1000. When I got close to the charge I use for a 300 win with a 210 bullet I had accuracy and great velocity. That was good enough for me and I stopped there.

This is probably a repost but I find this important. When I changed this load from RP or Win brass over to RWS brass it was HOT. I had to back off 3 gr of powder to make it happy again. This is due to the strength of the RWS brass and the fact it has less case volume. Then we tested our drops at 700 and 1000 with the new lower charge and brass. The drops were the same as the 3 gr heavier charge and RP / win brass. So I recommend RWS or Lapua brass and starting low with H-1000 and a 180 Berger. Probably 68 ~ 70 gr or so.

Jeff

 

[diriel]

Regarding lube and necking down, I use Lee lube. It is a white past. I like the RCBS lube pad. Roll the case on it, then use a brush to lube the inside of the case. I cheerfully admit that having to use a towel to clean off the excess on the case afterwards is a bit of a pain, but this stuff comes off pretty easy so it is not terrible. For me, this paste has been just about the best I have found. I did use some of that wax once or twice, and it was real good too, but it was a bit of a pain in the butt getting the wax off afterwards.

Happy shooting
Gary

 

[tresmon]

I'm drawing my reamer print...

What is the average neck dia on loaded winchester 7mm-300 brass?

Thanks,
Tres

 

[tresmon]

Anyone?

Loaded neck dia?

 

[Broz]

Anyone?

Loaded neck dia?

We are using RWS brass now. But I can tell you this.

WW case average neck thickness checking 3 of our old cases is .0135"

So, if you want a close guess, .0135 x 2 = .027" + .284" = .311"

Jeff

 

[Stonewall2]

I am using .300 Win brass to make 7 mm Rem Mag cases.

First run thru a .338 Win f.l. die to set the shoulder and then f.l. size with a 7mm Rem die.
Anneal necks before neck turning because the hardness -spring back of the necks now is slightly different.

The case now head spaces on the shoulder exactly before firing .


The necks will clean up at twelve and three quater thousand thickness in all the lots of Winchester .300 Win brass that I've used so far..


Glenn

 

[tresmon]

Thanks Jeff,Stone

What is the neck dia. on the RWS brass?


And guys what is barrel life on this one?

Anybody got a reamer for loan or rent?

Thanks so much,
Tres