M1 Carbine load data for sabots anyone?

[flydoc]

Ive seen several threads on 22 cal sabots on 30 cal rifles and have a bunch of 55 grain boolits and sabots that are telling me they are wanting to get together. I have experience in bolt actions with these, but not autoloaders. Have tried 12.5Gr 2400 with decent accuracy, minimal recoil, will eject ( flying only a few inches )but wont cycle. Cases seem to hold 13.6- 13.7 grains 2400 without compression at seating but have not tried a max loading. Have not tried other powders yet, figuring best to tap into the wealth of experience here first. Anyone have a load that they found successful? BTW the plastic did not separate from the boolit (sized 224) at 30 yds I picked for the test. ( Going to slow? I dont have a chrono)No key-holing. My 55 grainers are round nosed and feed fine when manually cycled.

[Mooseman]

http://www.eabco.com/Reports/sabot07.gif

[flydoc]

Mooseman,
Thanks for the load data. If I am reading the table right, the load I started with is at least at maximum pressure or even a little more. If that's the case, it isn't even enough to cycle the action and I have a single shot. The table lists 2400 (which I used),H-110, and AA #9. I wonder if any slower powders have been successfully and safely tried.

[Mooseman]

The problem I see with the data is the listed barrel length of 9.02 inches where a carbine barrel is 16.1 inches so a bit slower powder may be needed and a load worked up. I havent tried any in 30 carbine , I am loading some in 300 H&H for grins and to have a fast varmint round when big game hunting.
If I were to start developing a load I would use data from the old 5.7Johnson Spitfire or the .218 Bee and go with the IMR 4227 load decreased to 9.0 grains , then check for function, then a 9.5 gr load, then a 10.0 grain load,etc. with a 12.0 grain load being about Max. IMR 4198 could be tested at 10-13 grains as well. Start low and work up.
Rich

[Combat Diver]

I bought some .224 55gr JSP with sabots back in the early 90s (total weight 64gr). Just relooked in my log book and see that I used 12.7 gr of AA-7. I seem to remember them cycling my dad's carbine. Looking at the load data that I got with them has listed for the .30 Carbine, AA-7 starting load of 12 grs and max of 14 grs.

CD

[MakeMineA10mm]

I bought some .224 55gr JSP with sabots back in the early 90s (total weight 64gr). Just relooked in my log book and see that I used 12.7 gr of AA-7. I seem to remember them cycling my dad's carbine. Looking at the load data that I got with them has listed for the .30 Carbine, AA-7 starting load of 12 grs and max of 14 grs.

CD

Good post CD!

With a case of limited volume and a super-light bullet (which is what this amounts to), you're gonna have to go to faster powders for reasonable performance (cycling and increased velocity), rather than slower powders.

I've mentally toyed with this, but not actually loaded any. IMO, if that 55gr .224" bullet isn't going well over 2500fps, it's all for naught.

[Mooseman]

Good post CD!

With a case of limited volume and a super-light bullet (which is what this amounts to), you're gonna have to go to faster powders for reasonable performance (cycling and increased velocity), rather than slower powders.

I've mentally toyed with this, but not actually loaded any. IMO, if that 55gr .224" bullet isn't going well over 2500fps, it's all for naught.

If its NOT working with 2400 which is a fast powder why wouldnt you go slower powder like was proven in the Johnson Spitfire to work much better in both cycling, velocity , and accuracy in the Carbine action ???
The Spitfire ran 2650 to 2800 FPS mv with IMR 4227, where a normal Mil spec 30 carbine runs ~ 1950 FPS or less.
Longer barrels need slower powder to produce optimum results in Most cases.
A lighter recoil spring may help with the cycling problem too.

[flydoc]

I'm going to have to try 4227 and AA-7, and thanks for the advice. Ill report the results. I don't really want to lighten the recoils spring because I want to be able to just feed it it whatever I have. Im not trying to make it something it is not, just wanting to have fun. Minute of milk jug is just fine. I poured a bunch of 22 bator rounds and they sit deep enough and are round enough to emulate the contour of ball ammo and feed great. I wonder if I need to size them a little smaller or lube them somehow to get them to release from the plastic doomafloppy.

[psj12]

I have tried exactly what you are trying to do and could not get the 55 Gr to stabilize. I don't think the M1 carbine is twisted tight enough.

[MakeMineA10mm]

If its NOT working with 2400 which is a fast powder why wouldnt you go slower powder like was proven in the Johnson Spitfire to work much better in both cycling, velocity , and accuracy in the Carbine action ???
The Spitfire ran 2650 to 2800 FPS mv with IMR 4227, where a normal Mil spec 30 carbine runs ~ 1950 FPS or less.
Longer barrels need slower powder to produce optimum results in Most cases.
A lighter recoil spring may help with the cycling problem too.

Hey Mooseman,
2400 is not what I would consider a "fast" powder, because I am looking atthe entire burn-rate chart from Bullseye to 5010. It is faster than H110, but only a very small amount. It is one of the few (generally considered slow/magnum pistol powders) powders which are in the narrow band on a burn-rate chart which give good results in the 30 Carbine (from about AA#9 through, arguably 680/1680, which many would argue is too slow).

The difference between the Spitfire and a carbine loaded with a sabot round is the expansion ratio. The Spitfire has a .224" bore which all the gas must squeeze down. With a 30-carbine firing a sabot, there is still a .308" bore the gas is pushing down, so there is no constriction or funneling of the gas. This in effect, drastically reduces pressures. As the sabot/bullet combo move down the bore, the chamber is constantly getting bigger, therefore pressure is dropping precipitously, hence the need for a faster burning powder than the typical 30-carbinepowders.

The reason 2400 is not a good choice is because in addition to being too slow, it is a very bulky powder with big granules. AA#9 is almost identical in burning speed to 2400, but because it has very fine ball granules, more of it will fit in the same space; an important consideration with the tiny 30-carbine case. Even so, when taking into consideration the very large expansion ratio to bullet weight, a faster-still powder will be necessary.

When you say longer barrels need slower powder in most cases, you are right, except here we are working with one of the exceptions. The 30-carbine is more like the 357 & 44 Mags when shot from leverguns: most of the velocity is built up in the first 12-14", and the cases are just too small to get enough powder into to take advantage of any additional bbl length. It's an effect of the expansion ratio again.

[MakeMineA10mm]

I'm going to have to try 4227 and AA-7, and thanks for the advice. Ill report the results. I don't really want to lighten the recoils spring because I want to be able to just feed it it whatever I have. Im not trying to make it something it is not, just wanting to have fun. Minute of milk jug is just fine. I poured a bunch of 22 bator rounds and they sit deep enough and are round enough to emulate the contour of ball ammo and feed great. I wonder if I need to size them a little smaller or lube them somehow to get them to release from the plastic doomafloppy.

I've not heard of or tried cast in a sabot, but my gut tells me that no lube is necessary. Sizing, I guess, would depend on how well the inside diameter of the sabot accepts the unsized boolits.

[flydoc]

Ok , here is some news anyway. Got some 4227 but no time to load rounds yet. Went ahead and loaded few rounds with 2400 @ 13.5 grains and fired for function. All cycled flawlessly, cases ejected less than 2 feet away, recoil mild, primers showed no pressure signs. Looks like no tumblers, but accuracy was a shotgun pattern. Looks like all boolits came free from the plastic this time. Have not had chance to check intermediate loadings between this one and the prior 12.5 grain charge, that failed to cycle the action, but plan to do so and see if accuracy improves. Wish I had a chronograph.

[Mooseman]

AA7 is faster than 2400 which is faster than 110 /296/Imr4227 in that order. What I look at is the Pressure Curve of the powder as the bullet leaves the case and some slower powders have a a longer curve that develops the same velocity in a longer barrel with slightly more or slightly less overall CUP pressure depending on the powder. While this does happen in milliseconds , it can have an effect on a gas operated weapon like the carbine. It is why certain powders also work in a Garand to cycle it and others will not. Pressure, Impulse time, bullet weight ,barrel length, and Bullet/barrel friction all play a part in the equation . Even though the Johnson Spitfire is necked down to .224 it is shooting a similar weight bullet in a similar length barrel with an M1 Carbine action and parent case. Yes it will take slightly more Gas volume in a 30 Carbine Barrel to achieve similar results, but it is only used as a reference for starting points to test to solve a cycling problem. Thats the true fun of reloading and cartridge development , and once you get a winning combination , you log it in a binder or in the back of your reload manual(s) for future reference.
The OP had a problem and i gave him an answer based on 40 years of reloading/load development/testing experience with many types of weapons from Single shots to Full Auto guns. He is now having some success with cycling and I hope he continues to develop his Load IN A SAFE MANNER.

[MakeMineA10mm]

I totally see what you are saying, Mooseman, and I'm getting a sense you may be feeling attacked or disrespected. Not my intention at all, so I'm sorry if anything I posted came off that way. My resume is very similar to yours, but add in commercial bullet casting and reloading business for two years; otherwise we sound like twins...

I, too, am just trying to help the OP have success in a safe manner. The difference between our advice to him is that you are skipping the most important aspect of the problem at hand. All of the things you are bringing up are totally correct, when talking about bottleneck rounds (regardless of whether it's the 5.7 Johnson or the 50BMG). What you are missing is the effect of the expansion ratio when loading straight-walled cartridges. The Carbine is even trickier due to it's small capacity, gas-operation, and then adding the other oddity of the super-light projectile due to the saboted 224s the OP is loading. Combining all these factors means safe loading to get reliable operation and decent velocity and performance of the powder (consistent ignition and burn) equals going to a faster powder than is typically employed in the application.

Just ignore the expansion ratio and tiny case capacity for a moment. Pull any reloading manual and look up any rifle cartridge with a wide weight-range of bullets (say, the 30-06). Look up the 2-3 powders which give the highest velocity with the 200-220gr bullet. Note where they are at on a burn-rate chart. Now flip to the 110-125gr bullets for the same cartridge. (To be fair there has to be an equivalent relavent "spread" in the bullet weights from the 30-Carbine's 110gr and the saboted 55gr bullets the OP is working with.). Now, back to our reloading manual and the 30-06's best (fastest velocity) powders with the 110gr bullet. Go back to the burn rate chart and note their burning speed. Note how the "best" powders with the lighter bullets are faster than the "best" powders with the heavy bullets?

This alone means the OP should be loading a faster powder. Now, taking into consideration the expansion ratio of the straight walled cartridge, we are very safe with a faster powder. In fact, I say safer, because the weak resistence put up by that very light saboted bullet, combined with the expansion ratio of that round, using too slow of a powder may produce erratic ignition or even squibbs, which, theoretically could lodge a bullet in the barrel.

Now, I wouldn't get crazy and recommend a case-full of Bullseye, but moving down the burn-rate chart a small step from AA9/2400 to the next-faster powders would be my first move. That puts us in the VV3N38, HS-7 (if you have any left), True Blue, Blue Dot (I wouldn't use this powder in this application however!) area of the chart. Start low and work up carefully. AA7 is one more small step faster than those previously mentioned powders. Again, start low and work up. (Fortunately, someone already has posted data for the AA7 combination, and you could use those as a start for these slower powders.) I wouldn't go any faster down the burn rate chart than the AA7 burn-speed of powders, though. My gut tells me velocity would start to drop off at the max loads, as Mooseman has described. (You hit max pressure you can safely load to, but the velocity is slower than with a slower powder.)

Look at it this way, Mooseman: the high expansion ratio of the particular case we are working with, combined with the ultra-light bullets, has an effect of "sliding" your pressure curve down the burn-rate chart so that faster powders are in the sweet-spot, as opposed to what is typically used in this particular cartridge.

[perotter]

FWIW

I've loaded & shot a couple of 1000 saboted .224 in 30 calibers, but never in 30 carbine. The powders that worked the best for me had faster burn rates than what I use for normal loads. For example: with 30/30 I'd us IMR 4227 instead of IMR 4895.

[Mooseman]

I don't feel attacked or disrespected, I am only stating what I have learned from experience , part of which was with a close friend who became an engineer for Winchester and did load development, and we did some wild stuff back in the day of loads for silhouette and Military rifles and we made some Interesting discoveries by playing with many powders.
This is a discussion forum to gain Knowledge and share the same , so here goes... I hope the OP doesnt mind .
Using your reloading book ( I grabbed a Speer) , if you will notice there are certain powders that are used in Both light and heavy loads, the difference is The amount of powder is higher for the lighter bullet while still in the safe zone. Now , if you look at the 30 Carbine Rifle loads Vs 30 Carbine pistol loads there are some of same powders listed but also FASTER powders for the pistol that are not listed for the rifle. A .3 gr difference in powder weight in a pistol vs a rifle produces 500 to 600 ft less velocity with the same powder and bullet weight than it will in the Carbine.
Now throw in the Gas piston action of a semi-auto rifle and you have a variable that must be compensated for so it will function properly.
In most every case I know of a*** SLIGHTLY*** Slower powder worked where a faster powder did not where function was concerned and bullet weight was changed.
Compare the 300 H&H Magnum all the different bullets from 100 grain to 200 grain and only a few powders listed will be the same , the difference being the amounts, yet because of its Burn rate it works for light and heavy bullets both.IMR4350 is one for example and this is what I look at for versatility in a powder with only the amount being different. This being a bolt gun is not considering working a semi-auto action, so I can load a faster powder Like IMR 3031 with a sabot and shoot it without problems.
The reason I suggested the powder I did is because it has that versatility while being *slightly* slower to work the gas piston while still building a good velocity safely. The difference in burn rates between the powders I suggested from what he is using is less than the difference between Bullseye and Unique in burn rates. Miniscule , yet it can make a difference in function and performance.
I do understand what you are saying about faster vs slower powder, and we may be getting deeper Than we need to in this case, but I hope you can grasp my point where a variable is involved.
( I would Never recommend Blue Dot either for this cartridge) !

Rich

[MakeMineA10mm]

Well, again, I understand your point, but your still missing the most important factor here: expansion ratio. Perhaps this explanation by Dr. Ken Howell will make more sense than my ramblings:


Expansion ratio is an expression of how fast the burn space behind the bullet expands as the bullet goes forward inside the barrel — how much, IOW, that space expands per inch, for example, of the bullet's forward travel.

A barrel ahead of a cylindrical case has a high expansion ratio — a smaller-diameter barrel ahead of a necked-down case has a lower expansion ratio, because the smaller-diameter bullet has to travel farther to expand the burn space behind it by as much as a case-body-diameter bullet expands it in a much shorter forward travel.

In two barrels of the same length, the bullet's trip to the muzzle can quickly double the burn space in a cylindrical case (in about the same distance in the rifling as the distance from the primer vent to the base of the seated bullet), but the burn space behind a bullet from an extremely necked-down case may not double before the bullet reaches the muzzle of a very short barrel.

Another way to look at it is how many times the bullet's travel to the muzzle expands the burn space behind it in a given length of barrel, for a given cartridge. A .22 Long Rifle has a much higher expansion ratio than a .220 Swift — because the bore volume of a rifle-length Long Rifle barrel is several times as much as the net volume of the case's powder cavity. The bullet from a .220 Swift would need an incredibly long barrel for its travel to expand the burn space an equal number of times the volume of the Swift cases's net powder cavity.

To reitterate:
(a) Inside the loaded, unfired cartridge, there's a certain amount of space behind the bullet (between the primer vent and the base of the bullet)— nearly full or full of powder.

(b) When the powder burns, the bullet moves forward, pushed by the expansion of the powder gas.

(c) As the bullet moves forward, the space behind it (between the primer vent and the base of the bullet) increases with each inch or other increment of the bullet's travel.

(d) The space behind the bullet becomes larger than it was before all the fun started. It may or may not become twice as large as it was. If the case is close to the same diameter as the bore, the bullet doesn't have to go far to make the space behind it (between the primer vent and the base of the bullet) twice as large as it was in the unfired cartridge.

(e) A bullet from a cylindrical or nearly cylindrical case (e g .38-55, .444 Marlin, .45-70. .458 Winchester Magnum) doubles the space behind it in a relatively short run toward the muzzle.

(f) A bullet from a necked-down case — with the body of the case significantly larger in diameter than the diameter of the bore (e g .223, .25-06, 7mm Magnum, .300 Magnum) — must travel much farther down the smaller bore to increase the space behind it as much as the larger bullet (as in [e], above) increases it in a much shorter travel.

(g) The expansion ratio is the expression of relatively how much bullet travel it takes to increase the space behind the bullet from a caseful of space to a caseful plus more space.

[Mooseman]

Quote from Jan,1985 Guns and Ammo article...
"The terms "bore capacity" and "expansion ratio" are among the most confusing in shooting lingo, and difficult to explain in simple words. But they are important to all handloaders, especially when designing wildcat cartridges, selecting propellant powders, or specifying a new rifle, new barrel, or rechambering job.

Expansion ratio is the more comprehensible of the two. It is simply that number of times powder gases can increase in volume, by a factor equal to the original volume of the powder, from the instant of powder ignition to the instant the bullet clears the muzzle and "uncorks" the sealed propulsion system. Expansion ratio is occasionally used incorrectly as a synonym for "efficiency", in that high expansion-ratio combinations are said to be highly efficient, and low ones less so. That may be true in one sense, but low expansion-ratio systems are almost always high-velocity systems.

The "inefficient" smallbore magnums such as the .264 Win., 7mm Rem., and .300 Weatherby are all low expansion-ratio rifles, with ERs around 5 or 6. The smaller cartridges with more modest velocity potentials--.22 Hornet, .256 Win. Magnum, .222 Rem., etc.--rate much higher on the ER scale: from 12 to 15. They are more efficient in the sense that they extract more useful velocity and energy from each grain of powder, but they cannot deliver the sheer power of the low-ER cartridge. Expansion raio, obviously, varies with bore diameter, barrel length, and the relationship of neck size to powder capacity in the cartridge. If other things remain the same, a straight case has a higher expansion ratio than a bottlenecked one (which is really another way of saying that the bore will have more volume per unit of powder capacity in the case). Also, if all else is equal, a longer barrel gives a higher expansion ratio than a shorter one, simply because it has more internal volume and, thus, the gases evolving from the burning powder can multiply their volume more times before the bullet departs.

A firm grasp of the expansion-ratio concept makes a lot of things ballistically easier to understand--like, for example, why a .300 Weatherby must burn six times as much powder of identical energy-latent content to move a bullet of the same weight only twice as fast as an M-1 .30 Carbine can, even from a barrel only about two-thirds as long! This example involves 110-grain bullets, Du Pont IMR powders 4350 and 4227, respectively, (which do have the same energy content although they have different burning rates), and barrel lengths of 26 inches for the magnum versus 18 inches for the carbine.

Powder charges and approximate muzzle velocities are 90 grains and 4,000 feet per second (fps) for the Weatherby and 15 grains and 2,000 fps for the little M-1. In general, the smaller the ratio of powder charge weight to bullet weight, the higher the velocity potential of a hypothetical cartridge. It will, however, be a more expensive cartridge to load, less efficient in the customary usage of that term, with shorter case and barrel life at sustained maximum load levels, less flexible as to bullet weights in reduced loadings, and it will require a relatively longer barrel for satisfactory performance. Altogether, that's quite a bit of information to be gained about a cartridge which does not even necessarily exist from a simple bit of long division.

"Bore capacity" is really a sort of extension of the expansion-ratio concept, but it has been sadly kicked around in the gun press for so many years that the best that can be said is that shooters are confused about it. Cartridges have been accused of being "over-bore capacity", or simply "overbore", as though the quantity being described were inherent in the cartridge itself, which it isn't. It also involves barrel length, bullet sectional density, and the burning rate of the powder under discussion. With a barrel long enough, or a powder slow enough, no cartridge would be "overbore", and cartridges like the old wildcat form of the .25-06, which may have been badly overbore back in the '50s when the slowest propellant on the market was IMR 3031, are not necessarily so today, in the presence of Norma MRP, Winchester 785 Ball, or IMR or Hodgdon 4831. "Bore capacity", then, is not an absolute, but a relative, term. "

Some more info can be found Here , where the pressure curve and gas operated weapons are mentioned.
> http://www.frfrogspad.com/intballi.htm

[flydoc]

I appreciate the wealth of knowledge we have in this forum. I took some advice on powders and got some 4227. The AA#7 is nowhere to be found locally. I loaded test/function rounds from 12-15 grains of 4227 over the 55 grain sabot round ( 58.5 grains total weight) and was not looking for best accuracy yet, just something that would cycle the action and function in semi-auto. Previously I found a compressed load of 2400 @ 13.5 worked,without much accuracy. None of the 4227 loads cycled the action. Best 50 yd group was the 14 grain charge, a 4 in spread. Well that's not much fun . Guess the experiment was a failure . Cant imagine I would get better accuracy or cycling with the #7, so don't think I will go that route. Back to good-ole lead 120gr for me. Have to admit sometimes that theory and practice often differ, but "hope springs eternal". I bet that sabot at 15 grains was scooting along, though. Holes were round on all loadings , but the lower charges did not cause boolit separation from the obturator. None of the loads caused any pressure signs and all were soft shooting.

[Combat Diver]

Just found half box of the AA7 and sabot load down at my mothers (since 91?). I'm bringing it home and will run them over the chrony and post data later.

http://i48.servimg.com/u/f48/16/48/54/01/30_car11.jpg (http://www.servimg.com/image_preview.php?i=931&u=16485401)

Other bullet is the Speer Plinkster 100 gr 1/2 jacketed SP.


CD

[flydoc]

I did not have AA7 to test. Looking foreward to your data.

[flydoc]

OK, Combat Driver, I found some AA#7 and am going to try the 12.7 charge load and see what happens, will let you know if it cycles in my cabine.

[flydoc]

Success to report!. Traded for enough AA#7 to test the 12.7 grain load you suggested and the carbine runs fine on that. Groups 4 in. at 50yds so I'm thinking some tinkering might reveal some better accuracy but all-in-all its a good start. This load, along with the 2400 at 14grains gives me something to start with. Both were 4 in groups at 50 yds, and the holes are round at that distance. Besides, the testing is almost as fun as the blasting. Thanks. Looking forward to find out what your Chrony reads on the AA#7 loading, Combat Driver.

[Combat Diver]

flydoc,

Glad to hear thats cycling for you. I'll try and get the chrony out on Sunday. I'm still down in Texas this week.


CD

[Combat Diver]

OK, got the 20 yr olds out and fired a few. The few that I got to chamber (didn't trim the cases back then) cycled and avg velocity was 2419 fps. Also ran a few of the Speer 100gr half jackets and they went 2050 fps. I'll pull the bullets and trim back the cases at some point.

CD

[flydoc]

Did the projectiles separate or stay on? My short range ( 50 yds) tests produced 30cal holes so I figured the boolit was staying in the nylon insert. Have not tested at 100 yds yet. Im not sure whether to call the nylon obturator the sabot or whether the projectile/insert is called a sabot or just the projectile itself. Suppose it is just semantics. Maybe someone can clear that up for me.

[Combat Diver]

Flydoc,

Only saw .30 cal holes at 13 yds as I was just checking velocity and functioning. The sabot is the plastic holder of the bullet.


CD

[flydoc]

Here is a pic of the sabot 30 carbine loads I made. The boolits are 55grain, from the Lee 22 Bator mold. A standard 120gr LRN is included for comparison. 56372

[leadman]

My cousin had some of these sabots and a 22cal boolit mold that he wanted me to play with. (I was off work for awhile). This was at least 20 years ago.
I used 2400 and got decent results with the case full or even slightly compressed. I had some 45gr jacketed bullets that I also tried. The velocity was in the 2400 fps range with accuracy around 4" at 50 yards just like the results posted here.
I did wipe a little lube, either RCBS case lube or Lubriplate on the projectiles so they would release the sabot. Seemed to work as the 50 yard target holes were 22 cal.
My cousin was hoping for higher velocity but I think the case is too small and with the gas operation it is not a good balance.
I do remember shooting some of these leftover sabots in my 300 Whisper but don't remember how they worked and can't find the load data. May have to try it again as I still have some sabots.