LT-32 vs. N133 in the 6PPC

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Dave Rabin

New member
Some questions for those of you who have used both LT-32 and N133 in the 6PPC:

1. Have you found that that each powder works better in certain temperatures and humidity levels than in others? In other words, does each powder seem to have a preference as far as temp and humidity goes?

2. After trying both, do you have a preference for one over the other, and if so, why?

3. Also -- has anyone noticed differentials in performance -- whether in velocity or agging capability -- between the various lots of LT-32?

I am working with Lot 10 of LT-32 and have thus far found it more difficult to tune with than I did with N133, and am wondering if it might have something to do with where I shoot and/or some change in the powder's characteristics. Thank you.

Dave Rabin
 
I haven't shot 133 but have used LT-32 in my 6 PPC and 6 BR for over a year (lots #4 & #6). I'm in Northern Virginia so we get pretty wide temperature swings. In the PPC it has seen everything from 30 degrees last week to 90+ in August. As long as humidity stays low I'm not dialing much to temperature changes. My barrel shows defined nodes at 26.9, 27.7 and 28.3 with a 68 grain Ultra. Four depths have been tested so far: +0.005" in, touch, 0.005" & 0.010" off. For every charge tried it prefers touch. Now here's where the tuning comes in. When the air gets moist groups open up. I don't know the tipping point but it seems to occur over 70%. I'll need more wet days to figure out what the gun wants in those conditions.

All that said, I'm really impressed with LT-32. Mr. Murdica did a great service for benchrest by pushing these powders.

-Lee
www.singleactions.com
 
Dave, I have shot both and like both. However, If I could get Lot #1 of the Lt-32, I would use no other powder for the PPC's. Subsequent lots have not shown me the potential that Lot#1 did and N133 performs better than the newer lots of LT-32. That first lot was quite a bit faster than the newer lots that I have tried. N133 shows some variation from lot to lot, but not enough that one cannot tweak it to get the velocity that he/she desires. Although I don't shoot as much short range BR as I once did, I will use N133 in the future. Good shooting....James Mock
 
For those that want something faster, some friends, including Lou, have said that LT30 has given excellent results in the 6PPC. I have even heard rumors that some have blended LT32 and LT 30. Also, if you want to speed up a powder, dry it, and if you leave it exposed to very humid air, eventually it may slow down, depending on its original moisture content.
 
Dave,

I've had lots 3, 6 and 10. Lt32 has been good to me. I've picked up my last 6 HOF points with it. With that said some days it shoots and some days it doesn't. That's why I always carry 133 with me. I've not been able to pin point what makes it not want to shoot. But I suspect it has more to do with humidity then temp.
Personally if I can get LT 32 to work I will go with it instead of 133. At a match I'll shot both to see which one I think is working. Most of the time it only takes a change of 3 to 4 tents to keep LT tuned throughout the day. Many times I hardly have to change it at all.

As far getting the different lots to shoot, I've found that by weight they produce very similar velocities. However if you just go by volume, they can be quite different.


If you are shooting out west it could be a whole different story.


Bart
 
All,

Thank you very much for your replies; that's exactly the kind of information I was looking for.

Dave Rabin
 
I prefer LT30 myself. I think it's really good in a 6ppc. I haven't been able to shoot much this past year while I was building a new shop, but come spring time LT30 will be the first powder off my shelf. Lee
 
skeetlee said:
I prefer LT30 myself. I think it's really good in a 6ppc. I haven't been able to shoot much this past year while I was building a new shop, but come spring time LT30 will be the first powder off my shelf. Lee
Click to expand...

Lee,

I bought an 8 lb jug of LT 30 myself, but I haven't tried it yet! What kind of loads are you shooting with it?
Bart
 
Like Bart, I'm interesting in hearing about LT-30. Initial reports sound promising so I bought two 8-pounders. But I haven't broken the seal on either....LT-32 has been doing so well for me thus far there hasn't been a need. May be a good plan B if I can't wrangle the 32 in high humidity.

-Lee
www.singleactions.com
 
The question I have on LT-30 is are there any pressure signs in high heat? I know it's similar to IMR 4198 accept finer. Always heard 4198 was strong in the PPC until it got hot...then you were quickly backing down the load.

-Lee
www.singleactions.com
 
I have found in my limited experience that either 133 or 32 will shoot at a particular match. In most cases it is a big difference. Lt32 shot well for me at SS, but at IBS nats I could not get it to shoot but 133 did.
Bill
 
Bart said:
Lee,

I bought an 8 lb jug of LT 30 myself, but I haven't tried it yet! What kind of loads are you shooting with it?
Bart
Click to expand...

The LT-30 Chronographs 75 FPS FASTER than the Original T Powder

Orignal T-32 27.5 Gns =3284 FPS @ 90 Degrees 28% Hum,,2999 Bar Press

Lot #7 LT-30 27.5 Gns =3359 F P S @ 90Degrees,, 28% HUM,, 2999 Bar Press

Lot #10 LT-32 27.5 Gns =3253 F P S @89 degrees,, 27% HUM 3001 Bar Press

For every 1/10 Grain , velocity will increase 10 FPS with both powders

Thats with a 13.5 Kreiger ,, 22" ,, 35 Freebore Pacific reamer,, with My 67 grain 790 BT

LT-32 is closer to the Original T Powder. I M H O

Joe P.
Phx Az.
 
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I've shot Lots 1, 2, and 10 of Lt32. Lots 1 & 2 chronographed the same and lot 10 was approximately 100fps faster. Lot 10 shot very well in my rail gun at the last 2 Nationals I've shot in. Never had to touch the measure all day. It looks to me like lot 10 is dirtier. The carbon ring is hard to keep ahead of with all the Lt32 I have used.

Later
Dave
 
One word of caution, it is not so much that LT32 is dirty, but that 133 is so clean. For just about any powder, if you use the same cleaning routine that you have with 133, you will eventually come up against a carbon problem. I used to wonder why back in the day,Tony Boyer used to use IOSSO after every match...until I realize that he was shooting that lot of 8208 surplus known as T powder, which was a whole other can of worms from a cleaning point of view, as compared to the 133 that I was using. I know that it is not necessary to use IOSSO that often for LT32, but doing so at the end of aggs might be a good way to stay ahead of a potential problem. IMO this could probably be said of powder except 133.
 
I'm sold on Iosso Boyd. After we spoke I treated my barrel to it on a nylon brush (8" or so past the neck). The proof was in the bore-scoping....it works. I'll repeat the process every 100 rounds.

-Lee
www.singleactions.com
 
classcat,
Thanks for the very good info. Back in the day, I did a test of several powders based on using the same measure setting and throw technique. Although LT 30 seems to be relatively insensitive to case fill, I still think that it would be a good test to redo. One could set the measure for a safe but stiff load of the powder that gives the most pressure per volume. and then throw loads for the other powders, testing them all over the chronograph. Although there has been a shift by some shooters to weighed charges, some still throw, and I think that differences in density are worth being aware of. One thing that I would add to my old test would be an accurate weighing of all charges. That part could be done at home at the loading bench, once a measure setting had been selected. I think that we both know of a top shooter that mixes powder, and by using some combination of LT30 and LT32 I suppose that the burning rate of T could be duplicated.
 
Boyd;
I weigh each charge with a Chargemaster although i do use a Bruno when i throw charges and is accurate to +/- 1/10 Gn, but i have a click to weight ratio notes that i use.
I have shot Lt-30 @ 29 Gns The velocity was 3509 FPS and the groups were SMALL, but when they BLEW UP,, THEY BLEW UP BAD.
The cases were doing well , but I use an SB die with a #4 shell plate.
We call the blend of LT32 and LT30,,, LT31,, i am still tinkering with that one.
I have shot 322 and 18167 blend and i has it's own time and place that it will work,but thats another conversation.
I am also a firm believer in constant powder temperature storage and keep it @70-74 degrees and a humidity lower than 20%, but here in Arizona thats not hard to accomplish.

Joe P.
Phx Az
 
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Bart
When I first started shooting LT30 I learned very quick that neck tension has a real effect. Pressure wise that is! Its been a while since ive gotten to really shoot, and going from memory im pretty sure I was shooting the 30 around 27.5 to 28.3 with very little neck tension. I ruined some cases early on using the same neck tension that I would use with 133, and shooting the 30 above 28.5 grains. I don't recall exact numbers but I think im pretty close here.
Another thing I remember about shooting the 30 was that bullet impact didn't change on paper over a full grain of powder change. I was impressed with that as well as the accuracy in my rail. Im really looking forward to shooting some more here really soon. I have a new james Leder barrel chambered up, and I need to give it a good work out!! Lee
 
skeetlee said:
Bart
When I first started shooting LT30 I learned very quick that neck tension has a real effect. Pressure wise that is! Its been a while since ive gotten to really shoot, and going from memory im pretty sure I was shooting the 30 around 27.5 to 28.3 with very little neck tension. I ruined some cases early on using the same neck tension that I would use with 133, and shooting the 30 above 28.5 grains. I don't recall exact numbers but I think im pretty close here.
Another thing I remember about shooting the 30 was that bullet impact didn't change on paper over a full grain of powder change. I was impressed with that as well as the accuracy in my rail. Im really looking forward to shooting some more here really soon. I have a new james Leder barrel chambered up, and I need to give it a good work out!! Lee
Click to expand...
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Skeetlee
I just put on a new barrel. It shot very well with 133. Looks like it's time to try the LT 30. Thank you for the info! If I get a chance I'll shoot some tomorrow!
Bart
 
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