MS / MP200 equivalents

[oafpatroll]

I used MS200 for well over 20 years for 9mmP sport ammo first with jacketed, then plated and finally cast and powder coated bullets. It and occasionally MP200 worked perfectly for those applications.

When Somchem pooped the bed and my stock of MS200 started to dwindle I bought whatever S121 I could lay my hands on but have never been able to eliminate tumbling with my powder coated bullets. Have tried all the angles I know of to address it including running up and down the velocity levels, sizing up to the fat end of .358 for .356 bores and trying bullets above and below my standard 130 grainers without success.

Someone who shoots PC bullets said that he'd had the same problem and resolved it by switching to Titegroup. Clutching at straws I assaulted my credit card and bought >R10k of the stuff two years back only to find that it did the same.

Can anyone point me to a propellant that has characteristics that are a very close match to MS or MP that I can buy a bit of to try? I'm assuming that what I need is something that closely replicates their pressure curves but please feel free to chime in with any suggestions.       

[Tripodmvr]

From posts on other forums, I see that Lovex is popular for 9mm. Check the explosia website for loads. Find attached a burn rate chart is old, but still useful.

[oafpatroll]

From posts on other forums, I see that Lovex is popular for 9mm. Check the explosia website for loads. Find attached a burn rate chart is old, but still useful.

Thanks @Tripodmvr. Is the relative burn rate the most important parameter to match if I want to achieve a similar pressure curve? I understand that the faster the burn rate the steeper the curve and according to some apparently knowledgeable people on cast bullets too steep a curve is the likely cause of my bullets stripping.

[Tripodmvr]

MS200 - shotgun propellant and fast burning
MP200 - pistol

Titegroup is close to S121 in burning rate and I think the rather abrupt pressure rise is what causes the tumbling.

Herewith Lovex info attached.

[oafpatroll]

Thanks, I don't see the Lovex info though.

[Tripodmvr]

We have power down and the cell phone towers are battling. File was left behind.

[janfred]

You can try Unique. Works well in my 9mm's using 4.2gr behind 147gr CMJ's. Seems pretty close to MP200 to me.

[Treeman]

You can try Unique. Works well in my 9mm's using 4.2gr behind 147gr CMJ's. Seems pretty close to MP200 to me.

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Yes Unique seems a less dramatic propellant.

[oafpatroll]

Thanks for the suggestions. I have also been referred to Vectan Ba9 1/2 so will give that a whirl too if it's available.

[big5ifty]

The powder should not make the bullets tumble.

If the problem is happening with cast only, not FMJ, then it's definitely not the powder.

Twist rule applies to handgun bullets also, more so because of the low velocity and stabilisation RPM.

What is the length of the lead bullet that tumbles, compared to the jacketed that does not tumble, and what is the barrel twist.

[oafpatroll]

The powder should not make the bullets tumble.

If the problem is happening with cast only, not FMJ, then it's definitely not the powder.

Twist rule applies to handgun bullets also, more so because of the low velocity and stabilisation RPM.

What is the length of the lead bullet that tumbles, compared to the jacketed that does not tumble, and what is the barrel twist.

It is the powder without any doubt. I used exactly the same home brewed PC bullet and powder (MS200) recipe for years (20k odd rounds) in various 9mmP guns with perfect results. The tumbling, which results in a visible keyhole in approx 1 in 5 rounds, began from ammo made in the second half of a reloading session with everything but the powder and charge weight (S121) being exactly the same.

It occurs with fast the fast powders (S121 and Titegroup) but not with the slower ones (MS200 and MP200). This I have confirmed quite recently with samples of those provided to me by long suffering mates. What has been explained to me by a number of people with experience of the issue is that the peak pressure of the fast powders arrives quicker than the tensile strength of the lead or coating can accommodate and thus they strip the rifling. I never even had a hint of leading before with my PC bullets much less tumbling. It apparently doesn't happen with jacketed or CMJ because copper is substantially harder than PC and can therefore withstand the pressure peak without failing.

Makes sense to me based on my very extensive observations of a painfully large range of testing.       

[big5ifty]

The skipping of the rifling is a bullet problem, if the problem doesn't happen with jacketed.

The slower powder is only compensating for the problem.

Your lead is too soft.

When I first loaded my own cast PC bullets in .38 special, I was horrified at the shotgun pattern and jagged holes on the target. I put the handgun cast bullets on hold for a long time after that.

When I started casting for rifle, my first test was on a 375 H&H, and I also got the shotgun pattern. I then paid more attention to the lead, increased the hardness, re-tested in other rifles, and found that 16BHN was good for 2100 fps in the big bores. I shot that lead hardness in my 500 Jeffery at just over 2200 fps last week, the holes in the paper were cookie cutter.

By the time I started experimenting with lead in rifles, all my pistol CMJ were finished, and I used that same lead hardness to cast 9mm, .38 and .44.

None of them keyhole, not even the .44 which is .44 special with 13 grains from an ancient tin of S241 through a 8" barrel.

I did find that the lead hardness increased a few points a month after casting to the 16 BHN.

[oafpatroll]

The skipping of the rifling is a bullet problem, if the problem doesn't happen with jacketed.

The slower powder is only compensating for the problem.

Your lead is too soft.

When I first loaded my own cast PC bullets in .38 special, I was horrified at the shotgun pattern and jagged holes on the target. I put the handgun cast bullets on hold for a long time after that.

When I started casting for rifle, my first test was on a 375 H&H, and I also got the shotgun pattern. I then paid more attention to the lead, increased the hardness, re-tested in other rifles, and found that 16BHN was good for 2100 fps in the big bores. I shot that lead hardness in my 500 Jeffery at just over 2200 fps last week, the holes in the paper were cookie cutter.

By the time I started experimenting with lead in rifles, all my pistol CMJ were finished, and I used that same lead hardness to cast 9mm, .38 and .44.

None of them keyhole, not even the .44 which is .44 special with 13 grains from an ancient tin of S241 through a 8" barrel.

I did find that the lead hardness increased a few points a month after casting to the 16 BHN.

Interesting interpretation given that there is no problem if I use a slower powder. If the root cause is too soft a bullet how do you explain the fact that I've shot the same alloy (literally from the same melt) with not a hint of leading and outstanding accuracy in a .270 Win at up to 2000fps? I also use it in 38 and 357 without issue.

 

[Tripodmvr]

Did a simulation in QL to see what the 4 propellants that I chose do with 115 PMP JHP in a 5 inch barrel. Loads adjusted to give 34K psi. Distance down barrel at peak pressure, barrel time (miliseconds) and calculated speed are recorded below.


       
MP200       5,4mm  0,468m/s  1313
MS200       5,4mm  0,477m/s  1289
S121        5,9mm  0,476m/s  1281
Lovex D036  5,0mm  0,464m/s  1323

It seems as though Lovex is the slowest burning and gives highest speed. The distance down the barrel of 5mm means it was the slowest accelerating projectile. S121 at nearly 6mm shows that the acceleration is about 20% faster and could explain the stripping. MP200 and MS200 are much of a muchness and both gave good results.

[oafpatroll]

Did a simulation in QL to see what the 4 propellants that I chose do with 115 PMP JHP in a 5 inch barrel. Loads adjusted to give 34K psi. Distance down barrel at peak pressure, barrel time (miliseconds) and calculated speed are recorded below.


       
MP200       5,4mm  0,468m/s  1313
MS200       5,4mm  0,477m/s  1289
S121        5,9mm  0,476m/s  1281
Lovex D036  5,0mm  0,464m/s  1323

It seems as though Lovex is the slowest burning and gives highest speed. The distance down the barrel of 5mm means it was the slowest accelerating projectile. S121 at nearly 6mm shows that the acceleration is about 20% faster and could explain the stripping. MP200 and MS200 are much of a muchness and both gave good results.

Thanks @Tripodmvr. Very interesting.