7mm-33Nosler

Smokinghole

Well-Known Member
Joined
Oct 18, 2017
Messages
137
Bare with me here.

With the slightly shorter case and longer neck the 33 Nosler case seems ideal to neck down to 7mm. I know that the 28Nosler is available but a 33Nosler case necked down with a 195EOL or 180ELD-M loaded above the neck/shoulder junction will feed from an AICS mag and leave room to chase lands a bit.

33 Nosler Neck/Shoulder Junction: 2.131
Berger 195 Bearing surface + Nose length = 1.398
This gives a COAL ~3.529 obviously with some production variation from both bullet and case. This also gives a neck length of 0.329 for some flexibility. It'd be an easy reamer, and case forming can be done with a bushing die from Redding and a couple bushings. Neck turn/reaming would be necessary. You should be able to use a 28Nosler seating die (Forster Ultra Mic, my favorite) and the Redding FL S bushing die for case forming/sizing.

See any flaw in the logic? I know I can just chamber in 7STW, 7-300WM, or just get a 7RemMag. Heck 7mm Blaser is also available at a bit less case capacity, but dies for that would be custom orders for what I'm used to using. No belt, nosler (norma) brass, long neck, 35 degree shoulder, standard mag bolt face, and AICS mag feeding, what's not to like?
 
I see no flaws in your idea. think the 33 is the best of the nosler cases. played with it in 6.5 and 7mm on quick design and quick load you can average .100 shorter,5-6 grains less powder, more powder options, and easier to keep in unmodified action only loss is about 50- 60 fps
 
Yes, If you neck a .370" diameter 33 Nosler neck down to a 28 Nosler .320" diameter, you will make the neck .0357" shorter.
but the necks will still be longer than saami spec. by .016 for the 7mm. atleast on quick design
 
The neck on a 7SAUM case is .311 and if I in fact lose 0.0357 that puts the neck at 0.2933 which isn't far off at a 0.0177 difference. The 28Nosler has a neck of 0.276 according to the Nosler case diagrams. I don't know how the Nosler cases grow as I don't have one, I know the 35 degree shoulder should slow growth.
 
to me it is worth it not having a smith cut up my action or single feeding. many years ago I necked the 338 rum down to 30 didn't loose anything to the 300 rum except .120 shorter oal.
 
And you think it's worth making a Wildcat that has less capacity to gain .016" neck length?

I'd barely call it a wild cat. It's no more wildcat than those doing 7-300 WSM for the neck/brass availability. Plus maybe I'm doing something wrong but my cases typically get longer when I do a neck down. I just did a RP .300 saum case and it grew almost .007 from necking down.

Where did your 0.0357" neck length loss come from? I'm genuinely asking because my neck down cases gain length, I've done some neck up wildcats (6dasher to 6.5BRX) and they predictably lose length. Physically necking down is condensing the original neck, it has to either go into the shoulder or into a longer neck.

To me it's worth the price of a reamer all the same as a custom reamer is to people that want to set the 195s out in a 28 Nosler. This isn't highly technical wildcat case forming, not changing shoulder angle, or major case dimensions. Keeps the boat tail junction above the shoulder junction and in normal mags, plus no action customizing. The loss in capacity is minor in my opinion when looking at the positive benefits.
 
A case similar to your design criteria exists. Production brass available from Norma. Feeds from standard aics pattern mags without modifications.

Precision seater dies available From Forester at a street price of $75. Room to seat the long bullets to the neck junction. Standard magnum bolt face.

Case capacity is nearly exactly halfway between 7mm rem mag and 7mm Norma.

7mm Weatherby. I'm getting 2870 FPS over H1000 with 180 vlds. I'm somewhat short of maximum velocity because I like my brass, and that's where my accuracy node was. Scary accurate with 180vlds and I don't have the copper fouling issues some see in the long barrel 28 noslers.

Also, these charge weights of H1000 are still small enough to ignite reliably in cold (-4F tested) weather with 210M primers.
 
There are plenty of cases close but all are belted, if I wanted a belt I'd just get the ubiquitous 7rem. I just wanted to take a whack at something not belted. Cost to play isn't bad, a reamer is all that'll I need special or custom. Plus I don't want to have a mile long freebore like 7 Weatherby surely has. Now I can shed the belt that I don't need and still get performance and be close to the lands at normal mag length.

If we all settled for something that already existed I don't know how far beyond .308, .30'06, and .300wm shooters would have been able to choose. Many cartridges have come and gone. Many variations of a cartridge became more popular that it's parent case. Some guys probably drop more money on swapping scope mounts looking for the "perfect" set-up than I'll probably spend on this as a custom chambering. I do appreciate the "it's a useless variation" type responses.
 
A case similar to your design criteria exists. Production brass available from Norma. Feeds from standard aics pattern mags without modifications.

Precision seater dies available From Forester at a street price of $75. Room to seat the long bullets to the neck junction. Standard magnum bolt face.

Case capacity is nearly exactly halfway between 7mm rem mag and 7mm Norma.

7mm Weatherby. I'm getting 2870 FPS over H1000 with 180 vlds. I'm somewhat short of maximum velocity because I like my brass, and that's where my accuracy node was. Scary accurate with 180vlds and I don't have the copper fouling issues some see in the long barrel 28 noslers.

Also, these charge weights of H1000 are still small enough to ignite reliably in cold (-4F tested) weather with 210M primers.

What is the 7mm Norma you referenced?

A 7mm Weatherby has a neck that is about .040" longer than a 7mm Remington. That means the neck has about .6 gr more volume than a 7mm Remington. The body of a 7mm Remington is slightly larger. Any difference in powder capacity between the two is going to be in the brass, not the chamber.

You can take a 7mm Weatherby case, trim the neck about .040", and fire form it in a 7mm Remington chamber.
 
I'm guessing the 7 Norma mentioned is 300norma mag necked down. Or it's a variation of 308Norma Mag. I'd go the 7mm-300NM route if it weren't for the case head, I'd prefer a stronger action than what I'm planning to use with this Nosler.
 
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