Anyone own a 7mm 300 Win Mag?

[deadlift]

Our reamer is throated for the 180's-190's, most guys opt for the longer box. I should have clarified that.
Chris

 

[Broz]

Our reamer is throated for the 180's-190's, most guys opt for the longer box. I should have clarified that.
Chris

Yes, all I have ran through the ones I built are 180 Berger VLD's and 180 Hybrids. With my reamer the rear bearing surface is at the neck / shoulder junction when the
O-give is touching the lands.

Jeff

 

[Jfive]

Re: Anyone own a 7mm 300 Win Mag ?

Anyone thinking about adding the 35 degree shoulder to the 7mm 300wm. Not sure what your wanting out of the dies, kinda nice that you can get em for like 75.00 new.

 

[Broz]

I really like just using the Redding bushing dies for a 300 win and changing the neck bushing. Gives me lots of easy options. That's why I didn't mess with the shoulder.

Jeff

 

[cummin_un_glued]

Jeff, do you step it down with a single bushing or with multiple?

 

[Broz]

Jeff, do you step it down with a single bushing or with multiple?

I take about .010" or so steps to keep the necks straight. It is over kill but I have been using 3 bushings.

Jeff

 

[cummin_un_glued]

thanks for the info. i'm having one built right now. its already at the smith along with the new barrel just waiting my turn. i was about to buy dies brass and bullets and i planned to use the redding bushing die so i just wanted to see. the smith i'm using said his reamer was spec'd off of norma brass. have you used any norma in yours?

 

[Skyking]

Had some time to start doing some load development for the new 7-300 win. I think the gun turned out great. Really liking it. Thanks To Jeff for all his help and this thread. Ran into a few problem with the gunsmith, but I have my gun. Cant wait to get it out on the steel. Jared from APA rifles makes some of the best rings I have ever used. Really love them. And always you cant beat the Bighorn!

I remove the brake and run a Thunderbeast 30p-1 suppressor. Shooting suppressed really is the only way to go now. Tried H1000 and Retumbo. Both worked good, but was seeing pressure earlier with H1000. Only have 1Lb of Retumbo left and cant find it in stock anywhere. Here is what I have so far.

Macmillan Edge A3-5 Adj check piece
Krieger 5.5 contour 27inch Barrel
Jewell Trigger 1lb
Wyatt Box
Bighorn Sporty Action
APA Rings
APA Little Bastard
Thunderbeast 30p-1 Suppressor
Nosler Brass
CCI-BR2 Primers
CCI-250 Mag Primers
Berger Hybrid 180
Reamer .200 Freebore
.316 neck

H1000
74 Avg 3095
74.5 Avg 3157 SD 6
75 Avg 3162 Started seeing Pressure
75.5 Avg 3191
76 Avg 3215

Retumbo
73.5 Avg 3128
74 Avg 3152
74.5 Avg 3180 Started seeing Pressure Stopped

 

[cummin_un_glued]

Great looking rig ya got there. cant wait to get mine back and start shooting. did you paint the stock? I like the digital camo.

 

[Skyking]

No I had the whole thing build and painted. I just ordered all the parts and sent them off.

 

[garou22]

I have a 7mm 300 Win Mag. I'm not exactly sure what the chamber cast is, but I do know that my smith measured his reamer specifically for the Berger 180gr. VLD's. I have found that mine likes a seat depth of .130 and will put a .689 six shot aggregate at 200 yards with an average muzzle velocity of 3176 Fps off 76gr's of H4831. I found that it takes over 80 grains of H1000 and Retumbo to achieve similar velocities. I also noted that 76.5 grains of IMR 7828SSC produces similar velocity, but shows overpressure signs (Shinny Ejector impression on the base). 7828 was the only powder I've tested so far that showed any obvious visable signs of over-pressure. Ramshot Magnum barely crested the 3000Fps mark at the powder weights I tested.

Testing was done at an elevation of 3500Ft. Temperature was 45 degrees Farenhiet. I don't know the Baro. pressure of the day. Chrono used is an Ohler 35M.

As for dies: Redding series "S" bushing dies for siezing. buy the .300 Win Mag body and the .311 bushing. Total $70.00 U.S. I use a Forster Mic Seating die in 7mm Rem that my smith reamed with the chamber die used on the rifle. cost was around $50 U.S. with the reaming work.

My build is a Defiance 'Rebel' Action with milled to match 20 MOA picatinny rail, 30 inch Lilja 7mm 3 grove Sendaro contour fluted barrel with a Cooper Break, Jewel Match fully adjustable Trigger, mounted to an AICS 700 Long Action Folding stock. Funny thing about that folding stock... Turns out that without it, I would have to remove the cheek piece to remove the bolt - food for thought.

 

[Petersen]

As for dies: Redding series "S" bushing dies for siezing. buy the .300 Win Mag body and the .311 bushing. Total $70.00 U.S. I use a Forster Mic Seating die in 7mm Rem that my smith reamed with the chamber die used on the rifle. cost was around $50 U.S. with the reaming work.

QUOTE]


I did the same thing with my seater die. When it was just a 7mm rem mag die I would sometimes get runout over four thousandths and sometimes double that. I used my reamer and cut the 'sleeve' of the forster seating die and now all my loads stay under three thousandths. Worked really sweet and for someone learning to use a lathe it was an easy project.

 

[Wachsmann]

great looking gun...seem to shoot well also

 

[300stw]

i am having chad dixon longrifles blueprint and barrel my action right now, 27in brux #3, 9 twist, 317 neck .200 throat, should have it next week, cant wait