Working Up Non-Typical Loads

[RVTECH]

I have been reloading a long time - so long I am probably in the 'Top Twenty' of the veteran reloaders on this forum. Anyway for the most part I have taken it seriously, spent time studying loads powders, techniques etc. and for the most part have a fairly advanced understanding of how everything works, the relationship of powders to calibers, case capacity and pressure anyway I have pretty good working knowledge of the science of reloading. Recently however I have been looking into developing some light loads with lead bullets for 30-30 not only for my self but for a friend of mine who just bought his son a used Marlin and would like to be able for him get comfortable with it before moving up to hunting velocity rounds (which I will also be making). Anyway I cannot find much in the way of data for lead bullets other than using 7-8 grains of Unique with 130 - 150 grain lead bullets. I was wondering why other typical pistol data could not be used, for example - if I can load 16 grains of WW 296 with a 158 grain bullet (a 'standard' .357 load) and shoot it out of my Winchester Trapper, then why couldn't I use the same data in a 30-30 round with say a 150 grain bullet? I would be equating the nearly the same load as the .357 but 296 is not recommended in any rifle. Is it an issue with a bottleneck rifle case that changes things? Just wondering as this is a new arena with me and I want to approach it correctly.

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[bballer182]

For what its worth, I / we (the 458SOCOM community) commonly use W296/H110 for a wide variety of bullet weights 100gr-405gr. If you aren't familiar with that round it is a bottleneck rifle case, although, slight it is still a bottleneck. Max operating pressure has been set at 35k psi and best used with Large Pistol Magnum primer. H110/W296 is my third favorite powder behind the slower Re7 and IMR4198

 

[deadshot2]

Generally speaking the larger the case the more likelihood that a reduced load will become a dangerous load. The more room in the case the more the powder will fall away from the primer and then not just ignite in a controlled manner but detonate. Many will use a filler in order to keep the powder near the primer, reduce the amount of surface exposed to the ignition flame, yet not add an excessive amount to the total weight of the "ejecta".

It's tough to develop any load where there are no real starting points or ranges published, either by manufacturers, or other handloaders. In the OP, it would seem to me that taking a normal pistol load and merely transferring it to a rifle case is opening the door to all the normal perils of reduced charges. I think I would consider either trying the first few "non-standard" loads with the old "tied to a tree" test station. That or maybe someone has an ex that would like to test it for you

 

[RVTECH]

Thanks for the replies. In the meantime I did some more digging and discovered 'some' info and data on pistol powder loads in rifles and I learned quite a bit actually. There is not a lot of data but I learned there are a few powders that are acceptable for reduced rifle loads with most of them being of the flake variety as flake powders ignite easier and are more stable in reduced loads, and one of the reasons Unique was mentioned quite often. Actually there is some reduced load data (using pistol powders) in older manuals. Anyway I think I am now on the right track - carefully.

 

[bballer182]

Ah, yeah now that I think about it, my speer manual has a lot of reduced recoil loads in it. (Its the latest addition, 6th or 7th, if I remember right)

 

[beezer66]

I use Trailboss for subsonic loads. Trailboss is very light and uses up volume in the case. In a .308, 9.5 grains with a 170 grain RN bullet at about 950 to 1000 fps, through a 24" barrel. Kinda like shooting a .22, no recoil and quiet without a can. Trailboss is very forgiving to load, just don't compress it. 15 grains will fill up a .308 case.

 

[AMProducts]

Perhaps that should be a new reality show: NWFA's next top loader

Anyways, light loads can always be a huge crap-shoot. However, since by definition you are doing something that's low pressure, you're less likely to get into trouble if you do enough research. An FYI the lyman cast bullet handbook has a lot of great info on this topic, and should be a primary resource for you.

That said, top powders for this are going to be unique, 2400, lil'gun, and maybe titegroup or clays. You could maybe throw in blue-dot. What you want is a powder that has a lot of "elasticity", by that I mean a powder that has very consistent performance over a known pressure range. For these pressures, case capacity, bullet weight, I would look at unique, 2400, and clays as my top pics. I still don't like trailboss (buy me a beer one of these days and I'll tell you all about it). Since you're looking for something in a 130-150gr bullet weight, cross-reference with .357 max, it has some similarities in terms of bullet weight, and case capacity, and then cross-reference this data with .308 subsonic data (there is some that is published).

With any of these powders, if you go over 13gr you're probably going to be too hot.

The load I would start with: Hodgdon Clays: 7.5-9gr @150gr bullet

The next I would try is ~8-10gr of Unique @150gr


I think you're spot on with your mild 357 load spec, I would stay away from H110/W296. Lilgun is worth looking at but performs best in straight wall cases.

When you're working up loads like this, I highly recommend staying with short/light bullets, they simply shoot better. Also, if you don't already have a chrono, get one

What you should do when out at the range is fire batches, and look at the standard deviation, once that number starts to get under 20, it's worth perhaps loading more with that same charge and see if it shrinks (larger sample allows you to throw out a high/low that happens for no explained reason). You should notice that there's a specific range where SD's can get very low, and once you go above, or below they start to grow again. This is the "curve" I was talking about earlier and is very important to pay attention to.

 

[jib]

I load Blue Dot for a bolt action 308 Win with 125gr Nosler BT and LRPs This load shoots .75"@ 100yrds.
The barrel is cool after 10 rnds, this has been a good varmint load for me.

 

[SinisterSouthpaw]

Trailboss is the way to go. 99.999999999999% of documented "detonations" using reduced loads turned out to be pilot error---i.e. double charged cases.

 

[AMProducts]

I load Blue Dot for a bolt action 308 Win with 125gr Nosler BT and LRPs This load shoots .75"@ 100yrds.
The barrel is cool after 10 rnds, this has been a good varmint load for me.

Yea, I had an old load using 12gr of Blue-Dot with a 110gr hollow point. I had an old mauser that was rebarreled to .308 win, that thing, with that load would shoot 1" groups at 100 yards... I about crapped myself the first time I saw that. BTW, it didn't have no fancy sights, it had the original blade and notch sights on it.

Trailboss is the way to go. 99.999999999999% of documented "detonations" using reduced loads turned out to be pilot error---i.e. double charged cases.

I'm not sure how trailboss is the best solution to this problem, it seems the better course of action is to not double charge cases, and use powders that have better performance.

 

[RVTECH]

it seems the better course of action is to not double charge cases

I agree. It's an easy thing to check for.

 

[P7M13]

I use Trailboss for subsonic loads. Trailboss is very light and uses up volume in the case. In a .308, 9.5 grains with a 170 grain RN bullet at about 950 to 1000 fps, through a 24" barrel. Kinda like shooting a .22, no recoil and quiet without a can. Trailboss is very forgiving to load, just don't compress it. 15 grains will fill up a .308 case.

Who needs 300 Blackout?

Perhaps that should be a new reality show: NWFA's next top loader

Nah, people would watch it for similar reasons to why they watch hockey games. They want to see some trailer trash get blowed-up!


Amp, all this can be modeled for case and barrel, an interesting differential equation.

 

[2ndtimer]

Do you have a copy of Lyman No. 48 or No. 49 manual? They have lots of cast bullet load data for almost all centerfire rifles and pistols. Hodgdon also provides some reduced load data with H-4895 for many cartridges on their website. I have used Blue Dot for some reduced loads in the .223 Remington and got some surprisingly good accuracy, too. I was able to load down to .22 Magnum rimfire velocity levels with much reduced recoil and muzzle blast. (Not that regular .223 recoil is a problem, but sometimes muzzle blast can be.)

 

[Spitpatch]

Hey, Rv, don't overlook the lightly explored avenue in these posts toward lighter projectiles as well. 110 gr hollowpoints and even .30 carbine bullets shoot quite well in .30-30's, if one is wanting reduced recoil. Also, explore the bulky standby's for blackpowder cartridges (5744 comes to mind, and I believe Trailboss was mentioned).

Oh, (pointed hint here): The 125gr Sierra Flat Nose Hollow Point is the bullet that allows my 1948 vintage Marlin 336(Lyman Alaskan 2.5x, post reticle) to seriously challenge some of my fat-barreled bolt guns with heavy glass.

 

[jib]

(5744 comes to mind, and I believe Trailboss was mentioned).

Accurate 5744 and IMR sr 4759, both work well, and Accurate and IMR provide data.
My 308 Win BD load could be double charged, so one would need to look long and hard at the cases before seating the bullet. I do the same when loading any cartridge.

 

[RVTECH]

Hey, Rv, don't overlook the lightly explored avenue in these posts toward lighter projectiles as well.

THAT is the plan - as soon as Badman gets caught up. I am going to try their 135 gr.

 

[AMProducts]

Amp, all this can be modeled for case and barrel, an interesting differential equation.

It can... to a point, quickload does a good job of attempting to predict everything, but even the best models only get within a few standard variations of what the SWAG (scientific wild-*** guess) says it should be.

Modeling and calculating out the function of the gun system is actually pretty easy, and modeling the powder burn rate over pressure is also fairly easy based on geometry of the powder. However developing math to describe the interaction between the two is significantly more intensive than the level of differential equations I'm comfortable with.

The bulk of the estimations I come up with put the most value in case capacity, and bullet weight, in terms of safety. In general, it is safe to take the same case capacity and bullet weight, and move it over to a caliber of larger size. However, the converse is never true without weighting, (taking into account other factors like gun design, cartridge pressure, etc).