iGeocacher
09-13-2016, 08:28 PM
I looked around to see if this thread was already in play but I didn't find any likely contenders so pardon if this is in the wrong place and feel free to move it ;-)
I'm relatively new to bullet casting and somewhat new to reloading but I'm having a great time with it so far. I mostly target shoot at the range and plink. I live in the country where it's legal to shoot but over the years the farms keep turning into subdivisions and the neighbors get closer. So, I'm seriously interested in subsonic with a "can." Even for my .44 mag I'm shooting reduced loads just to save wear and tear on the gun and be slightly kinder to the poor soul next to me at the range when I take my cannon ;-).
Recently I've been on a quest to find a good subsonic combo for my 7.62x39 Romanian AK47. It started life as one of those "kits" purchased for $99 at a gun show. With the help of a friend who likes to put together rifles and some nice replacement parts I have a very nice looking rifle. It shoots very well for an AK. I've slugged the barrel and it mikes out at .301-.312. I started casting with molds for AK 7.62 rounds at the nominal .311 diameter. Had some leading until I got down to around 1500 fps with gas check. As I got lower, in velocity I started having cycling issues. I started with Lee's C312-155-2R but at that weight at a powder charge big enough to cycle the action adequately I was in the 1500fps range, nowhere near subsonic. Looking at other subsonic round data, I needed a heavier bullet. Since my bore was kind of large I tried their C312-185 mold for the .303. That helped but I was only able to shave off a hundred or two fps, still supersonic when the action started having cycle issues. Also, I started tuning the recoil spring by shortening it a bit. That helped but I could see I wasn't going to get within a couple of hundred fps of subsonic at that rate. Then I noticed the TL309-230-5R boolit mold. Now .309 is a bit too small for my nominally .312 bore though the lands do engage since the small diameter is about .301. I believe this mold is for the 300 Blackout (not sure about that but they list it on their rifle boolit page specifically for subsonic rounds.) It's a bit long for the AK 7.62 which wants OAL of 2.20 or less. When you seat it to that depth, it turns out that the boolit lube grooves (ALOX style) drop just below the neck so the boolit falls through and "sits" on the powder. I thought about using poly-fill if needed for "stuffing" but as it turns out, 15.7 gr of H4895 gives about 1.17cc fill which is perfect. Bullet base rests on the powder charge and all I have to do is crimp it (using factory crimp for 7.62x39 Lee die set) and I end up with an OAL of 2.19 and change. I'm getting 1050-1080 fps. Now the cycling is on the hairy edge but it does cycle. I may have cut a bit too much off the spring in previous experiments but a replacement recoil spring is only $12 so it's a cheap investment.
In any case, my initial results have been so promising that I'm seriously considering taking advantage of Lee's custom mold offering and paying the $175 plus "regular" price for a custom mold. All I'd want is to take their TL309-230-5R and up the diameter from .309 to .311 or maybe .312 and move the ALOX style lube grooves 0.2 inches toward the front which would allow a nice fit in the case with the crimp groove where it needs to be for the 7.62x39 case. The increase in diameter will also yield a slightly heavier boolit and that will allow me to increase the charge a bit while still staying subsonic. The slightly increased charge SHOULD help the cycling based on my experiments thus far. Also, I think the extra diameter/weight should add a tad more stability given the slower rotational speed of a subsonic round. I believe the Romanian AK's are 1:9 or 1:10 twist. It already has a threaded barrel so all I have to do is get an appropriate piston with spacer for my TI-Rant 9mm can and I should be able to use it for quiet plinking in my back yard without bothering the neighbors.
Anyway, I thought I'd post this here to get any comments/advice from the old hands and I'm especially interested in anyone doing subsonic loads for AK47's. I'm learning a ton from reading through Lee's and Lyman's manuals and experimenting. Who knew this would add so much fun to my otherwise enjoyable shooting avocation.
-dB
I'm relatively new to bullet casting and somewhat new to reloading but I'm having a great time with it so far. I mostly target shoot at the range and plink. I live in the country where it's legal to shoot but over the years the farms keep turning into subdivisions and the neighbors get closer. So, I'm seriously interested in subsonic with a "can." Even for my .44 mag I'm shooting reduced loads just to save wear and tear on the gun and be slightly kinder to the poor soul next to me at the range when I take my cannon ;-).
Recently I've been on a quest to find a good subsonic combo for my 7.62x39 Romanian AK47. It started life as one of those "kits" purchased for $99 at a gun show. With the help of a friend who likes to put together rifles and some nice replacement parts I have a very nice looking rifle. It shoots very well for an AK. I've slugged the barrel and it mikes out at .301-.312. I started casting with molds for AK 7.62 rounds at the nominal .311 diameter. Had some leading until I got down to around 1500 fps with gas check. As I got lower, in velocity I started having cycling issues. I started with Lee's C312-155-2R but at that weight at a powder charge big enough to cycle the action adequately I was in the 1500fps range, nowhere near subsonic. Looking at other subsonic round data, I needed a heavier bullet. Since my bore was kind of large I tried their C312-185 mold for the .303. That helped but I was only able to shave off a hundred or two fps, still supersonic when the action started having cycle issues. Also, I started tuning the recoil spring by shortening it a bit. That helped but I could see I wasn't going to get within a couple of hundred fps of subsonic at that rate. Then I noticed the TL309-230-5R boolit mold. Now .309 is a bit too small for my nominally .312 bore though the lands do engage since the small diameter is about .301. I believe this mold is for the 300 Blackout (not sure about that but they list it on their rifle boolit page specifically for subsonic rounds.) It's a bit long for the AK 7.62 which wants OAL of 2.20 or less. When you seat it to that depth, it turns out that the boolit lube grooves (ALOX style) drop just below the neck so the boolit falls through and "sits" on the powder. I thought about using poly-fill if needed for "stuffing" but as it turns out, 15.7 gr of H4895 gives about 1.17cc fill which is perfect. Bullet base rests on the powder charge and all I have to do is crimp it (using factory crimp for 7.62x39 Lee die set) and I end up with an OAL of 2.19 and change. I'm getting 1050-1080 fps. Now the cycling is on the hairy edge but it does cycle. I may have cut a bit too much off the spring in previous experiments but a replacement recoil spring is only $12 so it's a cheap investment.
In any case, my initial results have been so promising that I'm seriously considering taking advantage of Lee's custom mold offering and paying the $175 plus "regular" price for a custom mold. All I'd want is to take their TL309-230-5R and up the diameter from .309 to .311 or maybe .312 and move the ALOX style lube grooves 0.2 inches toward the front which would allow a nice fit in the case with the crimp groove where it needs to be for the 7.62x39 case. The increase in diameter will also yield a slightly heavier boolit and that will allow me to increase the charge a bit while still staying subsonic. The slightly increased charge SHOULD help the cycling based on my experiments thus far. Also, I think the extra diameter/weight should add a tad more stability given the slower rotational speed of a subsonic round. I believe the Romanian AK's are 1:9 or 1:10 twist. It already has a threaded barrel so all I have to do is get an appropriate piston with spacer for my TI-Rant 9mm can and I should be able to use it for quiet plinking in my back yard without bothering the neighbors.
Anyway, I thought I'd post this here to get any comments/advice from the old hands and I'm especially interested in anyone doing subsonic loads for AK47's. I'm learning a ton from reading through Lee's and Lyman's manuals and experimenting. Who knew this would add so much fun to my otherwise enjoyable shooting avocation.
-dB