Fullbore 12 ga. slug loads

[oldandslow]

Greetings all, 3/9/12

You all have been very helpful in getting me settled into smelting and casting. My problem now is what powder to use for a 770 grain truncated cone 12 gauge slug from Tom's molds at Accurate Molds. I live in one of the territories and only have access to a few powders. I have done some internet searches, especially at shotgunworld.com but they seem hesitant to publish fullbore powder date (understandably concerned about liability issues).

Blue dot powder keeps coming up, first with Dixie slugs and their 945 grain triball with 28 grains of BD, and jeager106 using 36 grains of BD with a 770 grain slug. Greg5278 likes IMR 4759 or 4227 which are not available to me.

So I stand a reasonable chance of getting some Blue Dot if my FFL decides he has enough buyers to order it. Other powders available include Win 231, Unique, and 700X which are probably all too fast. I also have some rifle powders, 3031 and 4046 which are probably too slow. I think I can also get Win 296 which is similar to 4227 on the powder burning rate chart.

Any ideas on a powder and load for my fullbore slugs in my Remington 870 with Mossberg 12 gauge rifled slug barrel?

best wishes- oldandslow

PS- I've already tried saboted slugs with a foster and shuttlecock from BPI. I've also tried the Lyman 525 grain slugs. No matter which tricks I try from here or the SGW website with different wads, trimmed petals, shot cards or filling the hollow base I can't get reasonable accuracy at 50 yards (about 6 inch groups). I have used the BPI Gualandi fullbore slugs and get 1 and 1/2 inch groups but they are expensive and have to come half way around the world to reach me.

[excess650]

Since we don't know where you are or what you have access to, check out thic brun rate chart:
http://www.hodgdon.com/burn-rate.html

It appears that you should be looking in the IMR 800x-H322 range. There are lots of powders in that range.

[oldandslow]

Sorry my first post was a bit long. As mentioned above I live in one of the US territories. The powders I have access to and mentioned above are Win 231, Unique, 700x, 4064, 3031, Win 296 and possibly Bluedot. Thanks.

best wishes- oldandslow

[longbow]

I doubt Win 231, IMR4064, IMR3031 or Win 296 are suitable. I have read that IMR4227 can be used under heavy slugs and some use it quite successfully. I have not tried it.

700X will be too fast except for very light loads but I wouldn't know where to start there.

Blue Dot should work for you. I have used Blue Dot for slugs from 1 oz. to almost 2 oz. with good results using heavy shot load recipes as a guide for the heavy slugs.

Unique may be decent but likely for relatively moderate loads. Ross Seyfried used 21.5 grs. of Unique in a Paradox gun under a 750 gr. slug with good results. Your slug is a little heavier and likely will have more bore friction so a charge reduction would be in order.

Another option if available is black powder. It is dirty but safe to shoot in measured dram charges and should do okay with a slug in a shotgun.

Not sure if that helps or not but it is all I've got.

Longbow

[eye shot]

With the barrel you have I would stick with Blue Dot because the barrel is too thin to use with real slow burn rifle powders. I have used IMR 4064 in my .410 slug gun but it has a real heavy barrel, bull barrel if you will and will withstand alot more pressure. 4064 does ignite well with 209 primers.

[oldandslow]

Thanks gentlemen, 3/11/12

It sounds like trying again to get some Bluedot from my FFL is about my best and only option. I appreciate Longbow's input on the Bluedot and have followed with interest your attempts to find the perfect heavy, fullbore slug on many of the internet forums. Jeager106 at Shotgunworld.com used 36 grains of Bluedot with his 770 grain slugs, is that a reasonable starting point or is that a maximum load based on your experience?

best wishes- oldandslow

[longbow]

I will have to try to find the charge I used under those heavyweights. I cannot remember. I think it was lighter than 36 grs. though. In fact I believe I used 32 grs. under the heavy slugs of about 800 grs. but I would have to check back to be sure.

What I do know for sure is that I used Fiocchi 2 3/4" low base hulls and Winchester 209 primers.

I believe the heaviest charge of Blue Dot I have used is 38 grs. in 2 3/4" Fiocchi low base hulls under 0.735" round balls. Recoil in a light gun got my attention so I didn't load heavier. No pressure signs, just got me punch drunk.

I often use equivalent weight shot loads for slugs if I don't have better information. The general consensus is that slugs generate less pressure than same weight shot load.

770 grs. is about 1 3/4 oz.

Just as an observation:

Alliant shows:

- 2 3/4" Fiocchi hull; 1 1/2 oz. shot; Win 209 primer; 36.5 grs Blue Dot; 10,300 PSI

- 3" Fiocchi hull; 1 7/8 oz. shot; Fio 616 primer; 34.5 grs. Blue Dot; 10,700 PSI

Depending on other components, Alliant lists Blue Dot charges from 38.5 to 39 grs. for 1 3/4 oz loads in 3" hulls and 32.5 to 36.5 grs. for 1 7/8 oz loads in 3" hulls.

My best guess at this point is that 36 grs. is max. or near max. depending on other components used. If the load has been pressure tested and shows lower pressure than max. I stand corrected.

Have you asked Jeager106 what components he is using?

Just remember that component changes can raise or lower pressure quite significantly and unpredictably.

I will dig around to see if I can find any better info for Blue Dot and heavy slugs.

Maybe turbo1889, Ajay or Greg will see this and have some advice.

Longbow

[missionary5155]

Good morning
I did alot of testing using just Unique. I learned alot about that powder with heavy objects.
One of which is when you go past the "useful & safe load combination" Unique will suddenly give a nasty pressure spike with the addition of just 2% of powder.
So I have to agree with many others.. for heavy objects start with Bluedot. Your shoulder will give out before your 12 bore will shake like the hammer of Thor.
Mike in Peru

[gvanzeggelaar]

I am currently doing the same thing as the OP. I have to slug my barrel and then am going to order the 770gr mold.
I will be using Magtec brass shells, and most likely bluedot powder.

Are 1/2" thick 11 gauge felt wads the right thing to be using for this application?

[turbo1889]

I would strongly discourage any attempt to use Win-296 for 12ga. full bore slug loads.

It is true that, that powder is the right burn speed for a full bore 12 gauge slug in the weight range in question but that particular powder unlike IMR-4227, IMR-4759, Lil-Gun, and to a certain extent 2400 will not burn correctly at the lower pressure levels that shotguns operate at and produces a dangerous combination of blupper loads and high pressure loads with the point inbetween the two extremes being an unstable teeter totter. Long story short if you get a stable burn the pressure is too high and if you reduce the pressure down to safe levels you don't get a stable burn. Or at least that is what my testing in 20ga. and 12ga. has shown so far. It can be used in the 410-bore but even then the range of safe and stable loads is a narrow margin in-between the two extremes.

The same by the way is true for H-110 and Accurate#9. H-110 is even worse and Accurate#9 isn't quite as bad and is the most stable of the three at lower pressure levels but still isn't suitable for any shotgun larger then 410-bore and possibly 28ga. (don't have a test set-up in 28ga. yet so can't be sure on that one).

As to other possibilities in that general burn rate range; the jury is still out on Accurate#4100, Allient 410, and Ramshot X-terminator.



As to the OP's original question: Blue Dot is his best bet from what I can see unless he left out a powder available to him that he did not list.

[oldandslow]

thanks again gentlemen, 3/12/12

If I ever can get my FFL to bring in Blue Dot then I will try some of Longbow's suggestions. And Turbo's suggestions on Win 296 were very informative. On paper 296 looked like it might work and it is available here but with Turbo's data it seems like a bad idea. It's really hard to work up a shotgun load without pressure testing equipment compared to pistol/rifle reloading. I guess that's why I defer to those more experienced. Thanks again. But the good news is that my Accurate Mold's 770 grain slug mold should be here this week so I can start casting up some slugs.
If I don't have any shotgun powder at least I can throw them at things to relieve tension.
best wishes- oldandslow

[turbo1889]

Don't get me wrong. I'm not saying that Win-296 is a BAD powder. It just doesn't have consistent ignition and stable burn at the lower end of the pressure spectrum that shotgun loads operate at.

Each different type of powder has its own set of quirks and burn rate is only one of the many different factors and behavior patterns of any given specific powder.

I would also ask if you can get black powder or a substitute in your area or not. You might not have considered it but the FFg stuff or equivalent "Rifle" granulation of a black powder substitute like Pydrox will work with the slug you are trying to shoot. A lot dirtier and more of a chore to clean your gun but better then lobbing them by hand. Considering the popularity resurgence of muzzle loaders over the last three decades or so you may be able to find FFg or equivalent substitute even in areas where it is hard to get more then a very narrow selection of smokeless powders and you should be able to obtain at least 1,100-fps velocity with it which isn't quite up to what is possible with heavy loads of the smokeless powders which give quality results but is still plenty hot enough of a load to kill almost anything the roams the earth.

[Ernest]

I had at one time a Explora double . I had some loads pressure tested trying to get the published velocities with a paradox bullet . Blue dot worked pretty well.

[Idaho Sharpshooter]

I load using the Lyman Sabot Shocker in 12 gauge. It conveniently weighs an ounce and an eighth (530gr), which makes it easy to do load work.

What length case are you using?

[Chicken Thief]

I load Vihtavuori N105 60gr under a 12g 690gr Modified Lyman Foster slug.