I bought a box of 300gr cast bullets to play with for my 45-70, due to the powder shortage I was starting with RL7 since I have a couple of cans in stock. My goal was a 1700-1800 FPS deer/plinking load. I loaded some cases up with 48 grains of powder, which left a little dead space in the case, maybe 1/4 of the case at most. The first round fired fine, the second round seemed to delay fire ( not much and I wasn't sure), third round was a squib. The primer fired and ran the bullet into lands, but the powder did not ignite.

You could see the grey flash on the powder, but it failed to ignite. I'm using CCI 200 primers, they seem to work ok on my heavier 430gr RL7 loads. Maybe week primers, but I'm thinking it was the air space. I guess I need to add some filler or maybe I'll try some varget.

I've used re7 in alot of cartridges...many lightly loaded and NEVER had a problem.
I can't tell you what the problem is but I can say that just doesn't sound like how "healthy" re7 performs. I was thinking the primers were bad or not well seated till you pushed the bullet into the rifling.
I'll follow the thread as it developers...interested in learning more here.

I have burned a lot of RL7 in both light and heavy loads, never had a problem. I use CCI200's and WLR primers.


I would not add filler to your RL7 loads, I don't use a filler with 10grs of Unique in the 45/70 case and don't have ignition problems.

Hard lubed bullets right? I've heard of over-lubed bullets causing problems with dampening the powder in the case but only with small case quantities.

Try raising the muzzle to vertical between shots. That should
show if it was the primer, or the airspace.

Here is another idea , IF your primer are not seated firmly all the way in to your cases that could be your problem .Firing pin hits primer , primer moves slightly inside pocket in stead off getting hit hard enough to " strike off" so no flame is sent out to light powder charge

Use 64 gr of Swiss 1.5 with Federal 215 primers and there will be no more ignition problems.

I've loaded for .45-70 and .45-120 using black powder in both and smokeless in the .45-70 as well. IMR- 3031 for that, as I recall. I used only cast bullets in all of them. I'm only guessing here but you MAY have contaminated the powder with lube from the bullets. In loading all of my BP cartridges, I always placed a wax paper disc between the bullet and the powder to avoid this possible problem. You might pull all of the remaining bullets and dump the powder then reload using a wax paper disc as I mentioned. The wax paper should not increase pressures appreciably in this case. Just a guess on my part that this I your problem. Also, are you sure that your primers are seated all the way? Using your fingers, you should be able to feel the primer seated to just below the cartridge head. I'm just guessing as to your problems. Good luck.
Bear in Fairbanks

I've always used Walter's Wads either .030" or .060" between base of a cast bullet and the powder. Then, compress the charge and seat bullet.

I think the .5" airspace is the problem if the powder is moved forward in the case or at an angle / . The same batch of primers worked fine with heavier loads of RL7 along with other calibers and was able to push the bullet completely into the lands. The lube is just hard lube on the Oregon Trail bullets, so that's not an issue. The primers are older ones but seem to function fine, maybe they are bit weak but it's hard to say. It could be this batch of powder is hard to ignite, but I think I'll move to another powder or some filler. Life is too short to play dangerous games and this combo didn't seem to work.

Try putting a small piece of dacron in the case on top of the powder.

Don't compress it but enough to fill the void,it won't take much.

I had a similar problem a while back.
300 gr cast and minimum loading of Reloader 7
Pull the trigger, heard the primer fire and half a second later got a discharge.
I came home and pulled all the bullets, threw them away and saved the powder.
I don't think I like the idea of minimum loads and space left in the case, won't be trying it again,

I just burned some R7 yesterday in my 45/70 39- 41-43 gr. with 420WLNGC. Used WLR primers with no problems. I have over the years fired quite a fair amount of Reloader 7 in many different cartridges but mostly 45/70 and .405 plus the Win. .458. Have not encountered one miss fire. Re7 in the 45/70 is going to be hard to beat. Once I used it , I didn't see much need for other powders I had used previously. Also 48grs. Of R7 isn't by any means a light load in the 45/70. Look else where for the problem unless the powder itself went bad, from moisture etc. good luck
Mouse

I had the same problem recently with a 350 GNR and IMR 4895 thought it was bad powder but it worked in other cartridges, next blamed the CCI primers, I was wrong it was a bad firing pin spring, it dented the primer but not sharply enough to ignite it completely, the bullet lodged in the barrel about 2" PITA and the powder was partialy burned only near the primer

Well, primers don't incompletely ignite nor does powder only partially burn.

Contaminated primers and squib loads are the problems here.

If air space was the problem none of my 45/70 loads would work.

28grs imr-sr4759 - 300-350-405gr cast
10grs Unique - 405 cast
14grs Unique - 405 cast
40grs RL7 - 405 cast and 405 Rem
25grs Alliant 2400 - 405 cast

The one load I have that has a full case - 59.0grs H4895 + 350gr bullet.

Never had a misfire in any weather or condition, never used a filler, never made sure the powder was over the primer.


Something else is up

Personally I think RL 7...sucks

but in the campfire spirit....PM me for my address....

and I will more than happily 'dispose' of it for you...

Sometimes you shoot what you want, sometimes you shoot what you can find. I have some varget that might work, but I'm not convinced it's a powder problem.



Same primer batch and powder batch worked fine with 430gr bullets at 45 gr, the only difference I can think of was the empty space. With 430gr bullet it's almost a full charge of powder. I naturally point the barrel down to feed a new round, so that would have cause the powder to move forward at an angle and an air pocket to form in the rear of the case.

That's my theory at this point anyway .

In rethinking about your problem, I'm leaning more & more to possible powder contamination by the bullet lube. In my note above, I used 47 gr. of IMR-3031 with my Lyman 405 gr. cast bullet in my .45-70 Sharps. In working this load up, I started at about 42-43 grs.
I never had a misfire, hang fire, etc. with anything I did. Looking at my burn rate chart, I notice that Rldr-7 and IMR-3031 are next to each other so I don't think you're out of normal load range. I still think I'd be looking at powder contamination.
Bear in Fairbanks

I reloaded the same cases and primers with 55gr of Varget, 1610 +/- 5fps out of my GG. A bit of unburnt powder, but it is consistent. I think the problems I had before were due to too much airspace, the Varget takes up a lot more room in the case.

RL 7 is a very popular powder for 45/70 and I have used it with no ignition problems in a Dago Sharps and my #1. But I did go to IMR 4895 and got better accuracy in the 1500-1700 FPS range pushing 405 gr jacketed FPs. Air space never appeared to be any problem but the 4895 does fill the case better. jm2c

I just had the same thing happen to me, searched and it lead me here. 47 grains of freshly purchased RL-7, Winchester cases (fired once and cleaned), CC-200 primers, and Hornady 300 grain hollow points. No lube as they are jacketed bullets. There was zero contamination of the powder or anything like that. I took a teaspoon of the powder and lit it with a bbq lighter. It took a second or so for it to ignite while open flame touched the powder. I was shooting a BFR revolver. After knocking the squib out of the bore, I tried a second cartridge with the same result. After clearing the bore a second time, I loaded factory ammo in the revolver and it fired just fine. The rounds were properly loaded, powder measured to exact weight, OAL and crimp the same on all. I think two things are happening here; slow hard to ignite powder with air space and weak primers. Still, that shouldn't happen and I don't know weather I should be mad at CCI or Alliant powder.

I switched powders on light bullets, and only use R7 on heavier 430 gr slugs. Delayed ignition is nothing to play with. The only way I would try it again is with cotton filler under the slug. Life is too short and I have too many powders for those games. Varget works pretty good on 300gr for me.