Anyone own a 7mm 300 Win Mag?

Got a chance yesterday to shoot my 7mm Practical. Rounds 21 thru 35 in new rifle. This was the first loading after fire forming 20 cases. Used a CED chrono.
168 Berger VLD
H1000
WLR primer
RWS cases
Barrel is 28 inches.

75.2 gr. 3113 fps
75.4 gr. 3138 fps
75.6 gr. 3156 fps
75.8 gr. 3180 fps
76.0 gr. 3231 fps
Groups were not good but 75.4 and 75.8 were tightest. Going to use these two charge weights and work on seating depth next chance I get. Work is getting in the way of everything. Not much info but all I have at the moment.

Hi Cockcroft, sorry I don't get much time to stop by LRH.com these days.

Please check the necks on fired cases, try to pass a projectile through the case mouth. Will give an immediate indication of case neck thickness. The projectile should pass through easily. Some brands including Nosler are too thick and need neck turning. But as someone else suggested, WW is the easy answer. Rem brass is not too bad either.

Fireform with trail boss to preserve barrel life.

Monitor rate of fouling while the barrel is still fresh. If it is a heavy fouler, this may prevent groups coming right down at the moment.

Seating depth 40 thou to begin with if using that particular bullet. COAL with 40 thou jump should be around 3.582". Occasionally, a smith will neglect to cut the freebore (the Practical reamer is a no throat design, second throat reamer must be used). This has caught one or two guys out.

If you need more help, my phone number is on our site, NZ business hours etc.

One step at a time.
 
Fella's,
When It Comes To Berger Bullets, And The VLD secant Ogive, I Strongly Suggest Reading Pages 100 And 101 Of Volume 1 Berger Bullets Reloading Manual. In Short: VLD Bullets Are Seat Depth Sensitive And That "Sweet Spot" Is Approximately .040 In WiDth. It Is Recommended To Load 24 Rounds In 6 Round Groups With Each Group Seated .040 Apart I.E.: Group 1 @ .010, 2 @ .050, 3 @ .090, And Group 4 @ .130 Off Lands.
I Applied This Advice To Both My 6.5X55 (140Gr) And 7 Practical (180Gr). What I Found Was That To See A Measurable Difference In Both Guns, Testing Had To Be Done Father Than 100 Yards, And I Wound Up Doing My Seat Depths At 200 Yards. At 200 Yds, Group Size WaS Visably Different And A Caliper Was Not Necessary To Discern Which Group Was Tighter. I Determined That The 140Gr VLD In My Remington 700 Classic 6.5X55 Swede Likes To Live .010 OFf The Lands While The 7 Practical Launching The 180Gr VLD Prefers A Whopping .130 Gap. NEither Gun Cared Where In That .040 Band The Bullet Sat, So I Wouldn't Waste The Bullets To Do Further Incremental Testing If I Had To Do It Over Again.
That All Being Said, The "Hybrid" Bullet Design Combines A Tangent Style Ogive Of Traditional Boat TAil Bullet Design With The Secant Ogive Design Of VLD Bullet Design. This Design, According To Berger Manual Page 102, Offers High B.C. without The Fickle SeOfat Depth Sensitivity That Us Common In VLD bullet Designs. I Have Not Tried Any of The Hybrid Offerings And Cannot Attest To THe Accuracy Of This Claim.

Hope This Helps.*
 
anyone try any of the nosler long range accubonds in this round. i have been shooting bergers, but have heard that the accubonds are doing wonders in other guns. i plugged in the data to my ab program and i would loose a little energy but transonic is further out
 
Hi Cockcroft, sorry I don't get much time to stop by LRH.com these days.

Please check the necks on fired cases, try to pass a projectile through the case mouth. Will give an immediate indication of case neck thickness. The projectile should pass through easily. Some brands including Nosler are too thick and need neck turning. But as someone else suggested, WW is the easy answer. Rem brass is not too bad either.

Fireform with trail boss to preserve barrel life.

Monitor rate of fouling while the barrel is still fresh. If it is a heavy fouler, this may prevent groups coming right down at the moment.

Seating depth 40 thou to begin with if using that particular bullet. COAL with 40 thou jump should be around 3.582". Occasionally, a smith will neglect to cut the freebore (the Practical reamer is a no throat design, second throat reamer must be used). This has caught one or two guys out.

If you need more help, my phone number is on our site, NZ business hours etc.

One step at a time.


Don't remember if I already posted this, but when you neck this round down make sure you anneal the necks. If you don't, the necks may not be soft enough to stay expanded after firing. So, the bullets will not slide inside the fired case as they will after annealing. The hard brass essentially springs back to a size smaller than the neck area of the chamber.

I continued to turn mine down further than needed because I did not anneal after reducing the neck size. Then once I annealed, I now have a lot more clearance than needed.

I have experienced similar results in necking other calibers down and forming brass; 17 rem from 204, fireball from 223, 22.243 from 243, etc.
 
Been reading and following this thread for awhile. I want to build a 7mm wildcat that has better speed and energy than a 7mm rem mag, but won't ruin a barrel like a 7mm ultra mag. I've been looking at a 7mm 300 win and I want the 37 or 40 degree shoulder. I am in the pacific northwest( tri cities Washington) area, and come from the flathead valley of Montana. I wanted to build on the new Remington 783, but have been unable to purchase a 7mm rem mag. My runner up is a savage or howa 1500. I want to purchase a barrel and do the rest of the work myself, with the help from family that's into this sort of thing. I can't find a company that makes the 7mm practical, or 7mm rogue where I can just get a 28" tube and not get the whole gun. Anyone know of anyone in Oregon, Idaho, Washington, or Montana that will just ream a barrel and not cost over 400-500.00 bucks?
 
Its gonna cost you deffinetly, you may be able to have a guy ream it for you, but you will have to send the action to them. You may be better off getting the scetch of the reamer and having one made so you can have someone you know ream it if you know someone. Other wise rent a 7-300 win reamer and get shooting
 
Been reading and following this thread for awhile. I want to build a 7mm wildcat that has better speed and energy than a 7mm rem mag, but won't ruin a barrel like a 7mm ultra mag. I've been looking at a 7mm 300 win and I want the 37 or 40 degree shoulder. I am in the pacific northwest( tri cities Washington) area, and come from the flathead valley of Montana. I wanted to build on the new Remington 783, but have been unable to purchase a 7mm rem mag. My runner up is a savage or howa 1500. I want to purchase a barrel and do the rest of the work myself, with the help from family that's into this sort of thing. I can't find a company that makes the 7mm practical, or 7mm rogue where I can just get a 28" tube and not get the whole gun. Anyone know of anyone in Oregon, Idaho, Washington, or Montana that will just ream a barrel and not cost over 400-500.00 bucks?

Jfive,
Dave Young, Owner Of "Young's Gunsmithing" In Tracy, Montana (Just Outside Of Great Falls) Is An Absolute Miracle Worker On Anything Metal. The Downside To His Meticulous Attention To Detail Is A Lengthy Wait. But, Price Is Fair, And Quality Is Phenomenal. He Built My Practical, Has Done A Magazine Well Mod On A Model 70 I Have, A Few Triggers Here And There, As WelL As A Number Of Projects For My Dad To Include A Custom BlueprintEd Tikka T3 LeftHand 6.5X55 Swede. You Will Not Be Disappointed, Unless You Want It This Week. He Can Also Obtain Any Barrel You Want From Any Of The Major Players In Aftermarket Barrels. I Highly Recommend You Give Dave A Ring, Tell Him Greg And Jim W. Sent You.
 
Been reading and following this thread for awhile. I want to build a 7mm wildcat that has better speed and energy than a 7mm rem mag, but won't ruin a barrel like a 7mm ultra mag. I've been looking at a 7mm 300 win and I want the 37 or 40 degree shoulder. I am in the pacific northwest( tri cities Washington) area, and come from the flathead valley of Montana. I wanted to build on the new Remington 783, but have been unable to purchase a 7mm rem mag. My runner up is a savage or howa 1500. I want to purchase a barrel and do the rest of the work myself, with the help from family that's into this sort of thing. I can't find a company that makes the 7mm practical, or 7mm rogue where I can just get a 28" tube and not get the whole gun. Anyone know of anyone in Oregon, Idaho, Washington, or Montana that will just ream a barrel and not cost over 400-500.00 bucks?


Pac-Nor in Oregon chambers it, they even do Pre-fit/ short chamber barrels.

The chambering is listed under "Wilcats" . I have owned and shot several of their barrels that shot well. Especially a .336 neck. .308 Baer barrel I had that was increadable. The .300 Ultra mag before the .300 Ultra mag.

PAC-NOR Barreling, Inc. - Wildcat Chambers
 
I was able to pick up a box of the new accubond long range hunting 175gr bullets, so It would be nice to be able to try them out and be ready to hunt next year. Pac nor has a few other 7mm wildcats that not many talk about. Does anyone still use the 7mm super mash. I have read that you can form brass from 300 win mag casings. It would be nice to start by reaming out a factory 24" barrel, and buy a longer one later.
 
I was able to pick up a box of the new accubond long range hunting 175gr bullets, so It would be nice to be able to try them out and be ready to hunt next year. Pac nor has a few other 7mm wildcats that not many talk about. Does anyone still use the 7mm super mash. I have read that you can form brass from 300 win mag casings. It would be nice to start by reaming out a factory 24" barrel, and buy a longer one later.

If You Get Things Rolling With Dave Now, You Will Have A Rig For Next Years Season. He May Be Slow, But Not That Slow. Dave Can Do Re-Chamber Work Or Raw Blank Barrels. My Practical Is A 30 Inch Lilja 3 Groove Sendaro Contour Fluted With A Break. The Joint Seam On The Break Is Blended So Well That It Looks A Single Piece With The Barrel. Dave Also Fluted And Step Threaded A Lilja AR Patrolman 24 Inch Bull To Fit A Wilson Combat Compensator for Me. The AR barrel Work Took Two Weeks. My 7 Practical, Due To Lead Times On The Action, Barrel, And Stock Took 9 Months. Cost On The Ar Barrel Was ArouNd $150, The Completely Custom 7 Practical Was 4100.
 
I was able to pick up a box of the new accubond long range hunting 175gr bullets, so It would be nice to be able to try them out and be ready to hunt next year. Pac nor has a few other 7mm wildcats that not many talk about. Does anyone still use the 7mm super mash. I have read that you can form brass from 300 win mag casings. It would be nice to start by reaming out a factory 24" barrel, and buy a longer one later.

If You Get Things Rolling With Dave Now, You Will Have A Rig For Next Years Season. He May Be Slow, But Not That Slow. Dave Can Do Re-Chamber Work Or Raw Blank Barrels. My Practical Is A 30 Inch Lilja 3 Groove Sendaro Contour Fluted With A Break. The Joint Seam On The Break Is Blended So Well That It Looks A Single Piece With The Barrel. Dave Also Fluted And Step Threaded A Lilja AR Patrolman 24 Inch Bull To Fit A Wilson Combat Compensator for Me. The AR barrel Work Took Two Weeks. My 7 Practical, Due To Lead Times On The Action, Barrel, And Stock Took 9 Months. Cost On The Ar Barrel Was ArouNd $150, The Completely Custom 7 Practical Was 4100.

Dave's 7Mm X 300 Win Mag Reamer Is Specifically Cut And Sized For The Berger 180Gr.VLD. that Doesn't Mean The Noslers Won't Work, Of Course. But It Might Take A Little Longer To Find Your Load For Them.
 
Still have not had time to fire form more then 20 cases for my 7mm Practical but my daughter did take it deer hunting and folded up two bucks in their tracks. 160 gr. Nosler Accu bonds.
 

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