.300/221 Rimmed?

[BitOfShush]

Been lurking for a while trying to pick up as much info as I can without asking a silly question... but can't seem to find out so here goes :confused:

I'm trying to work out reamer specs to make a .300/221 Rimmed out of .357 Max brass for use in a Martini Cadet rifle.

Now, I know that the .357 Max case has a head diameter of 0.379" vs the .221 Fireball's 0.376" so I want the larger head diameter to taper down to the .221 FB shoulder diameter of 0.361" and a shoulder angle of 23 deg.

Hopefully I can then use standard Redding .300/221 dies to create the brass out of trimmed .357 Max cases.

The PT&G reamer print I have been given is supposedly for a .300/221 Rimmed but differs in several (I think) important ways:
Shoulder dia is 0.3676"
Shoulder angle is 21 deg
Neck length 0.282"
Overall length from where rim meets body to end of neck is 1.340" (rim should be 0.60")
Leade (freebore) is 0.60"

I don't think this reamer has enough body taper for the Martini Cadet, which often has problems extracting fairly straight cases... even the .222 Rimmed in a Martini can stick with stout loads.

I'd like to specify the case tapers from 0.3776" to 0.361" with at least 0.10" freebore. I'd like to change the shoulder angle to 23 deg so the neck length will increase a bit to support heavy bullets.

Really appreciate any comments members may have on suitable reamer specs for a .300/221 Rimmed based on the .357 Max case... thanks :confused:

[d-mon]

Hello BitOfShush,

Here is what I would do if i where you:

I would get a few 357 remington maximum brass , maybe from different batch or brand, shot ones even better.Let say 2 or 3 of each.

Get a set of reloding dies in 30/221 like redding ones.
Trim them close to the lenght you would like to achieve
Full length resize the cases above, but with your olive assembly removed.
Then re expend the neck with a tapered olive or an expender.

Trim to the desired lenght that you want.

Send the cases to Pacific tool and gage so that they can measure them and grind a reamer for you. The chamber cut with that reamer will be slightly larger than the largest case of the batch, and you know that what ever case you will resize with these dies will work in that chamber.

As to changing the dimensions of taper, of the the body or shoulder, will involve getting some custom made reloading dies, which can be done but pushed the price up.

See what the other come up with...

But it is still an interesting project, and those martinis are so cute:smile:

Nick

[Artful]

You are aware there are already reamers and dies made for other wildcats based on 357 Max cases right?

http://www.mygunroom.com/dvgunshop/calibers.htm
quick google here
http://castboolits.gunloads.com/showthread.php?p=290416

Trim a new 357 maximum case to 1.36" and then size it with 300 Whisper die. This would give you a rimmed version of the 300 Whisper. Just use a standard 300 Whisper Reamer to chamber your 30 cal fast twist barrel - the Aussie's did a lot of this kind of stuff and Bertram even made 222 rimmed cases.
http://www.midwayusa.com/viewproduct/?productnumber=591825&utm_source=froogle&utm_medium=free&utm_campaign=652

[d-mon]

Well Artfull,

One way or another there is still the purchase of a reamer involved.
As Pacific tool can grind what ever you want at no extra cost, it would be better to have the proper reamer with the RIM.

With a standard reamer the job can be done, but anyway you have to either build a jig or solder the martini extractor onto the barrel and cut the rim with a lathe tool.:o

Just my thought.
Nick

[BitOfShush]

Finally got hold of some Remington .357 Max brass, and had a bit of fun trying out different case forming methods!

Tip No 1
You MUST trim to rough length and then anneal the brass before trying any resizing of .357 Max brass in a .300/221 FLS die... the case head size is subtly larger in the .357 compared to the .221 Fireball/.223 brass (0.379" vs 0.376").

See the first image for what happens when you don't anneal the cases first... I was SO lucky the case didn't jam fast in the die :eek:

http://i560.photobucket.com/albums/ss46/BitOfShush/30-221RimmedDevelopment2small.jpg

Tip No 2
Use plenty of very high quality lube... I found Redding Imperial Sizing Die Wax to be the best.

Tip No 3
It is best to use a pipe cutter when rough trimming the .357 Max brass, as it creates a nicely rolled edge... this helps the initial necking process start smoothly and evenly.

Tip No 4
Remove the expander ball before the first case sizing pass.
Start the necking process with one smooth steady motion of the press arm, then stop and lower the arm and apply more case lube before proceeding to resize the case body. There is a lot more effort required to size the body vs the neck.

Tip No 5
Insert the tapered neck sizing ball, re-lube the case and FL resize for a second pass all in one go. This time the case should move in and out of the die smoothly and without galling.

Tip No 6
Trim cases to required length in a couple of passes... I chose an overall case length of 37mm to give a much longer neck than the standard .300/221 case.
I think this will give better support to the longer 220gr-240gr jacketed projectiles as well covering some of the lube grooves in cast bullets.

The longer necked rimmed case also holds slightly more powder than the .300/221, so should squeeze a little more supersonic performance. Using Win 296 and filling right to the top of the neck, the .300/221 holds 24.7gr vs the .300/221R's 26.5gr... a difference of 1.8gr.

I'm quite pleased with the way the Rimmed Whisper turned out... just need to draw up the new reamer specs.

And as it is now a bit different from JD Jones' original, maybe it should be called the 7.62x37R :grin:

http://i560.photobucket.com/albums/ss46/BitOfShush/30-221RimmedDevelopment3small.jpg

[d-mon]

Congratulation for the job.
I have seen somewhere the method you discribe ...:rolleyes::smile:

If you can check the concentricity and neck thickness of different cases coming from different batches, just to make sure.
You might want to turn the neck as well to get the ultimate accuracy!

Good luck with your project, you are on the right track

Nick

[Mike-Sid]

Great job! Keep us updated when you get the reamer.

[JFettig]

You mentioned supersonic performance, you might want to check into the pressures that the cases can handle. I don't think .357 max is nearly the pressure that .223 is. The cases might not be able to handle it. It might be a good idea to section the base of a .223 case and .357 max case to compare dims.

Jon

[d-mon]

Hi,
I just had a thought last night.
Definitly check the thickness of your brass at the neck.
Mine is about 0.013" to 0.015". Anymore than that and each time you are going to size down with your die and size up again with the olive, you will be overworking your brass and reduce its life expectency.
It might be worth neck turning it down.

Or you could use a redding neck sizing die with interchangeable bushing to minimize the overwork.

Nick

[redtazdog]

Bellm makes barrels for the 221/357max whisper and i think he chambers other barrels too.
http://www.bellmtcs.com/store/index.php?cid=474
.
From the website
.300 Whisp-R Improved 12" Contender/G2 barrel & dies
Barrel and custom dies package $435.
10," 12," and longer lengths as available chambered to the Improved version of the .300 Whisper, either rimless, or rimmed cases made from .357 Rem. Max. brass.

.300 Whisp.-R Imp. is what the original .300 Whisper should have been designed as in the first place. The shoulder diameter is increased to .376", and the shoulder angle is a much more substantial 40 degrees. The rim of the parent .357 Rem. Max. brass assures positive headspace.

Shoots commercial .300 Whisper factory ammo, legal for Illinois handgun deer hunting.

The extractor is set up to accommodate both rimless ammo made from .221 FB brass or .357 Rem. Max. brass, both of which are available from me preformed & trimmed to length for this barrel on special order. Or, form your own cases.

.357 Max. brass must be annealed before forming. Annealed brass is on hand at $45/100 for you to form and trim yourself.

.300 Whisp-R formed and annealed brass, ready to load, $75/100.

No fireforming is required. Just load and shoot.

Price: Bellm custom blued barrel and custom CH-4D FL die set $435. Call to check availability.


.300 Whisper loaded Corbon ammo from Dakota Ammo
Check with Corbon to locate a dealer in your area selling .300 Whisper loaded ammo.


Illinois Corbon distributors and dealers


More details about .300 Whisp.-R Improved.

My spelling seems to have gone down the tube since I got on the internet, but, no, that is not a misspelling of Whisper.

What I have done is what should have been done to the .221 Fireball case in the first place. That is, establish a more pronounced shoulder to headspace on by increasing the shoulder diameter approx. .010" to the same diameter as the similar .223 Rem. based rounds such as .223 Rem. Imp. and the TCU's like the once popular 7mm TCU. And, the shoulder angle has been made the more abrupt 40 degrees like the TCU's.

Those shooting the standard .300 Whisper or those familiar with the round are aware that once you bump the neck diameter of the Fireball case to .30 cal., there is not much of a shoulder left.

Go figure...... neck diam. is about .330," shoulder diameter .360" and change, difference about .030-.035." Divide that in half for the radius, and you have a shoulder that is only about .015 to maybe .018" wide.... NOT MUCH!

While adding about .005" to the width of the shoulder is not much either, that combined with the more abrupt shoulder angle is a definite improvement in supporting the case against the blow of the firing pin.

Also, what I have done is cut a rim counterbore for .357 Rem. Max. Thus you have the best of all worlds with this type of cartridge.

You have a better shoulder to headspace on, the back up headspace point at the rim to regulate how much the shoulder can collapse when the firing pin hits the primer, and the convenience of shooting either rimless or rimmed ammo interchangably.

The reason for wanting to still be able to shoot rimless ammo is largely for those good folks in my home state of Illinois where this guy grew up as a pig farmer weilding a razor blade on the back end of boar pigs starting at about age 8. Thankfully, I learned to exercise more finesse carving steel than I did carving out supper. So much for the more colorful side of my history.

In Illinois, the .300 Whisper and the .30 Bellm are the only two bottleneck cartridges grandfathered in as legal handgun deer hunting rounds. There are those who are more enthralled with the mystique of the miniscule Fireball case and its practicality compared to the larger and somewhat faster .30 Bellm.

Thus I have crafted the .300 Whisp-R Imp. so that standard .300 Whisper ammo can be fired in the chamber, making it legal for use in Illinois for deer. The letter of the Illinois regulations stipulate what ammo can be used, not the chamber. So if you have a box of commercially loaded Cor-bon ammo, you are "good to go" hunting deer with it.

For other purposes, or if you want to stretch the envelope a bit, you can make cases out of .357 Rem. Max. brass, which I also make and supply if you want to use the rimmed version.

Accuracy is the main interest, and with my throating, expect these barrels to be tack drivers that are very comfortable to shoot.

While Illinois deer hunters were first in my mind for this chambering anyone from any state that is interested in diminuitive, high performance rounds like this will certainly enjoy it.

[BitOfShush]

Thanks everyone... some very good points raised.

D-Mon
In my enthusiasm to post my results, I didn't acknowledge your help with the methodology :wink:

Regarding neck thickness, the .300/221R made from .357 Max brass measures 0.010" vs the .300/221 case made from old reformed 223 Win brass measures 0.0115".

.300/221 cases made from 221 Fireball brass measure from 0.085 to 0.0115" (they definitely need neck turning, I'm not surprised at the lack of concentricity given the extreme sizing from .224" to .308").

Stands to reason the .300/221 case has a thicker neck, as it is originally part of the shoulder.

These measurements are taken with a Mitutoyo digital vernier, not the best for measuring neck sizes... I'm getting a digital pipe micrometer soon, which will be far more accurate.

Jon
I sectioned both a .300/221R (discarded non-annealed case) and a standard .300/221 FB, and there is indeed a slight difference in case thickness at the head. Measured as best as I could just above the web, the .357 Max case wall thickness is 0.0395" vs 0.0400" for the .300/221 FB created from Winchester 223 brass.

Note the amount of burrs around the flash hole on on the Remington .359 Max case!

The biggest difference was in the case head thickness just below the primer pocket... the .357 Max brass is MUCH thinner than the 223 brass at 0.0480" vs 0.0780". The radius between the head and the case walls was also different... the .357 Max case was exactly R1.0mm vs R1.25mm on the 223 case.

Not sure how much difference R0.25mm and 0.005" wall thickness will make in overall case strength, but the much thinner case head below the primer pocket is a worry. It would be VERY wise not to exceed moderate .300 Whisper supersonic loads :eek:

Redtazdog
Thanks for the links... I'm sure I'm just reinventing the wheel with this .300/221R cartridge...

I'll see if BellM have a standard reamer print, but I'll also have some more fun designing my own :grin:

BoS

http://i560.photobucket.com/albums/ss46/BitOfShush/30-221RimmedWallThicknessComparedco.jpg

[JFettig]

quick results on sectioning those cases!

It looks like your .223 case has had its flash hole uniformed. I'm sure the .357 max cases could use that.

Its hard to say about the radius, its not that much of a difference but could make a difference. The one thing to notice is that the wall thickness increases before it gets to the radius. Did you measure both just above the radius?
That .0005" wall thickness wouldn't make any difference I'm sure, but the case head thickness might be a problem. I seem to recall that federal .223 brass had a case head thickness of around .050". You could section a few different common brands, RP, LC, Federal, and FC(yes, FC and Federal might be different, .223 vs 5.56).

One more thing to measure: the primer pocket depth. I seem to recall that pistol primers aren't as long as rifle primers. I'm not 100% sure this is true.

Regarding case length and reamers. I am pretty sure that the clymer 300/221 reamer is made for a 1.4" case length(from their old print anyway that they use to have up). Are all other outer dims the same?

Jon

[BitOfShush]

Flash hole uniforming is definitely on the list :wink:

Did a bit more measuring of primer pocket depth on both cases :

.300/221 FB 0.1165"
.300/221R 0.1180"
Difference 0.0015"

Yep, measured the wall thickness at the tangent of where the web radius joins the wall... did so a number of times to get a consistent reading... tricky!

One thing I didn't take into account is that this rimmed cartridge will be used in a Martini Cadet falling block action, and therefore the entire case will be supported by the relatively thick chamber walls... unlike the bolt and AR15 semi-auto actions where part of the rimless case head projects from the chamber and is enclosed by the bolt/extractor. Hoop strength of the relatively unsupported rimless case is crucial to maintaining primer integrity in high pressure loads.

Checking the 2006 Winchester Reloading Guide reloading catalog (which features CUP pressure readings on many cartridges) I discovered on that the .357 Maximum 180gr FMJ load develops 46,900 CUP vs the .223 Rem 55gr FMJ load's 41,000 CUP... so it would seem the case is plenty strong enough if well supported.

I'd say the weakest link is the primer... I had also heard that small pistol primers were slightly shorter than small rifle primers, but I can't find any confirmation on the web.

Indeed, while Sinclairs list both a large rifle and large pistol pocket/depth uniformer, they only list one small rifle/small pistol uniformer.. which suggests they are the same length.

There is an interesting article by James Calhoon at:
http://www.jamescalhoon.com/primers_and_pressure.php

He sums up:
"What does all this mean to the reloader?

- Cases that utilize small rifle primers and operate at moderate pressures(40,000 psi) should use CCI 400, Federal 200, Rem 6 1/2, or Win SR. Such cases include 22 CCM, 22 Hornet and the 218 Bee. These primers are also used in heavy handguns such as the 9mm., 357, etc. Other cases that use the small rifle primer can use the above primers only if moderate loads are used. Keep to the lower end of reloading recommendations.

- Cases that utilize Small Rifle primers and operate at higher pressures (55,000 psi) should use CCI 450, CCI BR4, Fed 205 and Rem 7 1/2."

I already have 1000 Federal SR Match primers, so will try them out first for cup thickness and consistency of ignition in sub-sonic loads... they seem to get a good rap from those picky benchresters!

Yes, aware of the issue with the case length of Clymer's reamer... PT&G are on the ball and specs are correct for their standard .300/221 reamer.
Interestingly, the 300 Whisper is also referred to as the 7.62x35mm in military sniping circles!

Some dimensions for the rimmed cartridge will change from the standard .300/221 FB (freebore, throat angle and case taper) to better suit cast lead bullets in a falling block action with less than stellar extraction.

I will complete the drawings over the next couple of weeks and send to PT&G for feedback... and then post here.

Thanks again for your help :smile:

BoS

[BitOfShush]

Spent a bit of time today making up some dummies to check freebore requirements etc and just thought I'd share them with the group:

http://i560.photobucket.com/albums/ss46/BitOfShush/300-221RimmedBulletSelection.jpg

[LouBoyd]

It looks to me like the 32-20 Winchester cartridge has just been re-invented. At least it's similar in shape and case capacity. TC used to offer the 32-20 as a standard Contender barrel for use with 308 diameter bullets, 10" twist.

It seems to me that these cartridges:
30 Luger (14.29 grain capacity)
30 carbine (21.0 grain capacity)
30-20 (21.7 grain capacity)
32-20 (22 grain capacity)
have been pretty much ignored for use as subsonics, arguably because of the lack of suitable strong actions to use with long heavy bullets. The 300 Whisper's capacity is more than necessary even for 240 SMKs.

[Thunderbolt]

G'day BoS, I have a Martini Cadet set up as a switch barrel with barrels in 17Mink and 20/357max. I'm watching this thread carefully as one of my future projects was hopefully to be a 300 Whisper Rimmed using 357max brass. My current project is a 310/357mag with the original barrel.
The thinking behind the 20/357max was to use standard reamers and dies, to eliminate the cost of custom dies and reamers which are quite substantial here in Aus. The chamber was cut by my local gun plumber with a standard 204R reamer run in short to 357max length and a rim recess cut in the face of the barrel. The reloading dies are cheap Lee ones. I trimmed the base off them to the right length. That was all easy and then came the usual problems you find with wildcats. as you discovered 357max brass is really hard and must be anealed before necking down. The next problem was the difference in diameter at the base of the case. The sized 357 brass would not fit in the chamber because of that few thou interference fit. I tried sizing down the solid head on a case but that was a wasted effort. So back to the Gunsmith and had him lap out a couple of thou from the rear of the chamber till the FLS max cases slipped in. Problem solved .I have the barrel stamped 204 short rimmed and its now up and running and slaying rabbits.
I believe from my experience that for a 300 whisper rimmed I would just have a chamber cut with the standard reamer and a rim recess cut to suit the max brass. Them I would use 300/221 dies and a 357mag shell holder. You already have the case forming sorted out- just give you G'smith a couple of your cases so he can lap out the first 0.200 of your chamber to suit your brass.
If you decide to go the custom reamer route then PTG are really good to deal with. There was no problem at all getting the 17Mink reamer from them.
I have assumed from the CBE bullet that you too are in Oz.
Keep us posted:wink:

Cheers

[Seddo]

How cool is this, someone else thinks the way i do. I have 2 x 22R martinis and a 357mag martini and have bene thinking about trying to get a whisper style round chamberded on a rimmed case. I was planning to use 222R cases instead of 357mag but either way who cares.

Let us know when you have it sorted, i would be happy to contribute to the cost of the reamer if i was allowed to get a barrel reamed with it. I looked at a thompson contender just so i could buy a whisper barrel but would prefer to use a martini.

[Thunderbolt]

G'day Seddo, BoS is probably still waiting on his reamer from PTG, takes at least 3months to get one. Hopefully he will keep us posted when he's got it going.
I have a Contender frame and MGM barrels are easy to import but like you I would prefer to do one on a Martini.
357 Max brass is cheaper and stronger than 222 rimmed brass, its downside is that its really hard and must be annealed before necking down

T'bolt

[amafrank]

You guys might try checking with Dave Manson at Manson reamers. He's been making some oddball stuff and I got my 300-221 reamer from him. His stuff is all top quality and the customer service is better than any of the others I've dealt with.

From all I've read the small rifle and small pistol primers are the same outside dimensions with the thickness of the cup and material hardness being the only difference. Its the large pistol primers that are shorter than the large rifle as they share diameter too. That means loading the 357 max cases with small rifle primers is a very doable thing and recommended if the pressures are up there. I know guys who load small rifle primers in a number of high pressure handgun rounds as a standard procedure.

Looks like an interesting round to fiddle with and I was at the bluing guys shop today looking at a few max's he had on the bench and thinking how well they would do for a whisper type round.

Frank

[BitOfShush]

At LAST, the .300-221 Rimmed reamer has arrived :grin:

Sent PTG three formed .300-221R cases to take measurements from using their optical comparitor, also measured the neck thickness of 20 357 Max cases as well as 20 formed cases to ensure the reamer neck diameter was correct.

The normal 2-3 month custom reamer timeframe was lengthened by a couple of communications stuff-ups and then the Go/No Go Gauges were found to have been made up to the wrong specs! Once notified, PTG acted very quickly to rectify the problem however, and new gauges were promptly sent out.
Very pleased with their customer service overall...

http://i560.photobucket.com/albums/ss46/BitOfShush/300-221-Rimmed-Reamer-Web.jpg

Because of the nature of headspace in a falling block action (and potential slack in the linkage pins) I elected to have the rim gauges made up at .060" Go and .065" No Go.

NOW... I want to use this project to determine whether my chosen .300-221R specs for case length, freebore, neck clearance and leade angle will work with cast projectiles yet still allow longer jacketed projectiles (SMK etc) to be chambered down a standard Martini Cadet action ramp... I don't want to be grinding down the ramp and weakening the action :eek:

Some interesting barrels being produced at Truflite in NZ:
http://www.truefliteriflebarrels.co.nz/13544/index.html

I have an old Omark 44 .308 win heavy target barrel with a shot-out throat but otherwise great bore ($20 at a Gunshow!) that would be just perfect as a 'test mule'... the heavy profile will easily turn down to the Cadet's 1" external profile and .750" x 14 tpi barrel tenon.

Twist is 1:9.5" so it may not stabilise the really heavy slow stuff but I can then determine whether I like the round enough to stump up for a nice match grade 1:8" barrel.

I will post again when I have something to share... but as Captain Oates once said "... I may take some time" :wink:

[d-mon]

Hello Bitofshush,

Are you based in Nz?
I am in Hamilton myself.
Your project seems to go well , even if it takes a bit of time.

I have a 300 whisper based on a cz action.
I love it.
I am working on a 458socom project, it takes some time as well(more than a year now).

Let me now if you want some receipes to try in your martiny.
The 180 gr hornady round nose should do quite well in your barrel,( if you have a bit of rifling left).

Good luck.

ND

[Archangel]

I actually joined this site due to your Martini 30/221 MAX.....
I built one 7 years ago on a Martini, it has a 25 inch barrel and measures dead on 30.5 inches OAL....
I use Gary Little 240gr flat base soft points on top off 10 grains of WIN 296....
Sometimes extraction is a little sticky...
I have a 50 Alaskin with a BMG throat with a 1-8 twist in exactly the same set up...
I will post a picture if your interested....in my little bullpup....

[Archangel]

http://www.facebook.com/album.php?aid=2046583&id=1385311414

[Seddo]

Great to see the project is going again. I am doing something simular as well.

[Seddo]

Well my project is getting closer too. The MAB barrel arrived last week so i now have everything except the extractor. I will start pulling my 222R martini apart over the next few weeks and get started on the rest.