7mm-300 Win Mag

[Long Range]

I have researched all about this wildcat and would like some advise or info for selecting a reamer. I see that several guys here have one and would like to know if leaving the shoulder angle at 25 deg is better than improving to 30 like the 7mm Practical. Also would it benefit from taking what case taper is in it out and just make it stright walled. I think this would be a great cartridge since I have already got some 300 winny brass. Any advice on this would be appreciated.

 

[Derek M.]

I have researched all about this wildcat and would like some advise or info for selecting a reamer. I see that several guys here have one and would like to know if leaving the shoulder angle at 25 deg is better than improving to 30 like the 7mm Practical. Also would it benefit from taking what case taper is in it out and just make it stright walled. I think this would be a great cartridge since I have already got some 300 winny brass. Any advice on this would be appreciated.

Personally I think a 5 degree difference is negligible and you won't know the difference.

 

[IdahoCTD]

If you leave it standard you can use a .300wm bushing die or a .300wm FL dies and a generic Hornady neck die. If you change it then it's all custom for a FL die.

 

[Long Range]

Sounds like it would be better left alone for the availability of dies. What would you recommend for the freebore to be able to shoot the 162 Amax and the 168-180 bergers.

 

[IdahoCTD]

Send a sample case with the bullet seated where you want it.

 

[Long Time Long Ranger]

Why not do a 7mm STW. Over the counter, cheaper, faster and a better long range cartridge.

 

[Broz]

I have done 3 so far and love them. We have well passed the throat life of some of the larger 7mm's like the RUM and STW. I prefer leaving the 25 degree shoulder. This makes the choice of dies easy. I use Redding comp bushing dies for a 300 win and simply step down necks by reducing bushing size until I am at the needed bushing for 7mm. I also feel there is some inherent accuracy from the 300 win case as we are seeing excellent accuracy from all 3 rifles. So I would leave the taper alone and keep it simple and also for easy extraction. We have done 9 twists and throated for 180 Bergers. The velocity is plenty good from a 28" tube with H-1000 for propellent easily in the 3150 to 3175 area @ 4000 ft.

Hope this helps to answer your origional posted questions.

Jeff

 

[Derek M.]

Why not do a 7mm STW. Over the counter, cheaper, faster and a better long range cartridge.

Actually, I convinced a friend to buy an STW, telling him that he could find factory ammo, brass, and, well, that is not the case. We can't find brass anywhere nor factory ammo. He'd prefer components so he can use handloads.

Some years ago I remember seeing quite a bit of factory 7STW ammo at Bass Pro. But for the past 3-4 years, nothing in that caliber from any manufacturer. I'm hopeful, for his sake, that he has better luck than me, since he lives in CO.

 

[Long Time Long Ranger]

I have had no problem finding brass for mine or any other components. The shorter winchester case will give you a little more seating room and less than 100 fps difference from what I remember when we did the wildcats off the 300 winchester 35+ years ago. The STW just makes it simple with easily and cheaply available dies and brass without necking and fireforming. barrel life is no difference with either.

 

[Long Range]

Thanks Broz that's what I was thinking I read the hole thread you started on the first 7-300 win mag that's what gave me the idea. I do have one more question I was wondering if 1-8.5 or 1-8.7 twist would be to fast for the 162-168 because I see that Berger may come out with a 195 that would be a thumper. Also do you go with a tight neck or a no turn on your 7-300.

 

[Broz]

Thanks Broz that's what I was thinking I read the hole thread you started on the first 7-300 win mag that's what gave me the idea. I do have one more question I was wondering if 1-8.5 or 1-8.7 twist would be to fast for the 162-168 because I see that Berger may come out with a 195 that would be a thumper. Also do you go with a tight neck or a no turn on your 7-300.

Long Range, you are asking the wrong guy about little bullets, I gave them up long ago. But I think you would be fine as long as you didn't exceed the bullets capabilities as far as twist and velocity are concerned.

I had PTG do my last reamer and it is awesome. They kinda screwed up a bit and gave it .050" more throat length than I requested but in the end it was perfect as the rifle likes the bullet .050" off the lands and was a consistant .2 and .3 MOA rifle at 300 yards. Now I am thinking the extra .050" will play right into the new 195's length.

My reamer is a no turn neck, I have had zero issues with necking down to 7mm and the neck thickness.

I will admit that I lost a little fire for the round with the introduction of the 230 Bergers for the 300 win. But now with this new 195 and the proposed BC's I am thinking the 7mm-300 just grabbed another gear.

The way the 180's shoot I can't wait to try some of the 195's. My buddy took a porcupine at close to 1100 yards in some light wind with his.

ps: I HIGHLY recommend a hart tube. The Harts have 6 lands and it induces less stress on jackets.

Jeff

 

[Long Range]

Broz do you remember what your throat or freebore is for your reamer because I may call PTG and try to get one. Also I was looking at the Broughton 5c barrels that's what my smith recommends but I will check the harts out.

 

[bigngreen]

Broz has these 7mm-300's dialed in, I've watched one of them whackn away at a 8in gong and it was looking stupid easy at close to 900 yards. Super sweet, even if it is a 7mm

 

[Broz]

O-give of bullet, to head of case is 3.032" with a 180 Berger VLD. This leaves aprox .150" of bearing surface in the case when the bullet is touching the lands. But seated at .050" off the lands you have .200" of bearing surface in the neck. The necks on a 300 win are about .206" so this is perfect for case fill which is needed with RWS brass.

All the rifles have shot well with some jump. The first one is .115" off the lands. This might be important if you do decide to shoot some smaller bullets.

The Broughton 5C is a great tube too. We have a couple in 300 win that are awesome shooters. But the Harts have been really good to us lately and with the increased twist rate I think 6 lands would be better.

Jeff