Need help! 359-640 vs 360-640 and 359-125 vs 360/640L

[Michael J. Spangler]

Hello!

I was hoping someone might have pics of these two sets for comparison.

I own the 359-125 and the 359-640

I’m considering getting the other two moulds mentioned but I was hoping to see them side by side. Or if someone has detailed blueprints which sometimes float around here.

Thanks for looking!

[Michael J. Spangler]

Anyone?

[farmbif]

what exactly do you want pictures of? I have the mp359125 from an old group buy and also the mp360640.

[farmbif]

miha usually has detailed drawings and pictures on his web site

[BK7saum]

I will see what I have. I may be able to pist pic of mold blocks side by side for comparison. i don't think I have all 3 but might.

+1 for checking MP website.

[Michael J. Spangler]

I would really like some side by side pics of the bullets. Or overall measurements.
I want to see how the crimp to meplat length is vs the ones I have.

[KVO]

Weights:
NOE 135gr solid/128gr HP
MP 359-135NLG 135gr solid/130gr HP
MP 360-640 155gr solid/ 145gr HP crimp to meplat .345"

MP 359-640 170gr solid/ ~158gr big HP
Crimp to meplat .330" short/ .380" long
I tied up a Dan Wesson cylinder from bullet pull once seating long and hence only use the shorter seating depth now, obviously revisited crimp as well. The shoulder on the 1st/long groove is barely there and I don't think it actually does much as a shoulder in practice. Also my LG brass HP and NLG 359-640 both have about .355-.356" max diameter on the nose and crimp grooves opening to. 358" on the drive bands if that matters to you.
The MP ~.358" molds can get confusing. I also have thehave 359-135 RNFP (not pictured) and there are a few more variations in circulation I haven't seen in person yet.
I don't have a 360-640Light to compare. Not sure if just t the driving bands are shortened or the nose profile scaled down as well. The 359-640 double crimp groove seems to be more popular on the site but I've had more consistent accuracy from the 360-640 single crimp groove. The 360-640 will work in most 9mm pistols but it's the ragged edge of fitting in that application IMO.

[Michael J. Spangler]

Weights:
NOE 135gr solid/128gr HP
MP 359-135NLG 135gr solid/130gr HP
MP 360-640 155gr solid/ 145gr HP crimp to meplat .345"

MP 359-640 170gr solid/ ~158gr big HP
Crimp to meplat .330" short/ .380" long
I tied up a Dan Wesson cylinder from bullet pull once seating long and hence only use the shorter seating depth now, obviously revisited crimp as well. The shoulder on the 1st/long groove is barely there and I don't think it actually does much as a shoulder in practice. Also my LG brass HP and NLG 359-640 both have about .355-.356" max diameter on the nose and crimp grooves opening to. 358" on the drive bands if that matters to you.
The MP ~.358" molds can get confusing. I also have thehave 359-135 RNFP (not pictured) and there are a few more variations in circulation I haven't seen in person yet.
I don't have a 360-640Light to compare. Not sure if just t the driving bands are shortened or the nose profile scaled down as well. The 359-640 double crimp groove seems to be more popular on the site but I've had more consistent accuracy from the 360-640 single crimp groove. The 360-640 will work in most 9mm pistols but it's the ragged edge of fitting in that application IMO.

Awesome info thank you. I think I really just need one of each to play with.

[KVO]

Awesome info thank you. I think I really just need one of each to play with.

I keep running into that problem...

I think the 360-640 is a great design and like it enough that I have both 4 cavity HP and a 6 cavity solid. I keep teeter-tottering on the 360-640L. There is a forum member here who reports consistent <2" at 50yd from a target revolver that bullet. My only caveat is that if the HP design is the same as the full size 155gr version it's going to over expand and have very limited penetration- Or maybe a great short range varmint bullet? The full size version HP has decent size round pins taking about 10gr out of the nose cavity and works well for 950-1050fps. The short cup point is actually a penta and does well at magnum velocities. Might still come unglued out of a rifle.

[SSGOldfart]

very well done KVO

[Michael J. Spangler]

I keep running into that problem...

I think the 360-640 is a great design and like it enough that I have both 4 cavity HP and a 6 cavity solid. I keep teeter-tottering on the 360-640L. There is a forum member here who reports consistent <2" at 50yd from a target revolver that bullet. My only caveat is that if the HP design is the same as the full size 155gr version it's going to over expand and have very limited penetration- Or maybe a great short range varmint bullet? The full size version HP has decent size round pins taking about 10gr out of the nose cavity and works well for 950-1050fps. The short cup point is actually a penta and does well at magnum velocities. Might still come unglued out of a rifle.

I’ve found that the penta shed petals when moved too fast. The cup expands like a JSP out of a rifle.
The penta is great up to pretty warm pistol loads or target loads that are moving a little faster from the rifle.

I like the 359-640 and wonder if the 360-640 is a little light in HP form also. Might be great for pistol work. It should expand better than the 359-640 does from the snubby.



Here it is with about 3.5 grains of bullseye.
Unfired. Snubby. 4” and 16” barrels. Into clear ballistic gel.
My guess is 1000 fps or so from the 16” barrel.

[KVO]

The closest to a real snubby I have is a 2.5" S&W mod. 19- so "cheating" on the velocity and also u. Similar results to yours though in that barrel length can make a tremendous difference. 359-640 big pins or penta pins did very nice with 6.5gr CFE Pistol (pretty close to Unique burn rate) out of the shorter barrel. But again well into light magnum pressures. My benchmark alloy is 20:1 for everything when starting and then tweak if needed. Keeping the antimony out or at the very minimum balanced with tin does a decent job keeping the bullet blowups at bay. I'll put up some more data once I find it.

[Michael J. Spangler]

The closest to a real snubby I have is a 2.5" S&W mod. 19- so "cheating" on the velocity and also u. Similar results to yours though in that barrel length can make a tremendous difference. 359-640 big pins or penta pins did very nice with 6.5gr CFE Pistol (pretty close to Unique burn rate) out of the shorter barrel. But again well into light magnum pressures. My benchmark alloy is 20:1 for everything when starting and then tweak if needed. Keeping the antimony out or at the very minimum balanced with tin does a decent job keeping the bullet blowups at bay. I'll put up some more data once I find it.

So zero antimony will keep it together even at the higher velocities. Keeping those petals from shearing off?

[KVO]

So zero antimony will keep it together even at the higher velocities. Keeping those petals from shearing off?

To an extent yes. You still need a conservative HP cavity geometry. Up to about 1400fps a shallow cup point penta will hold together. About 1150-1200fps is the limit for the bigger deeper pins and that's pushing it depending on the side wall profile.
These were 160gr out of a .40, ~1000 fps black, chrome ~1150

[KVO]

Photo dump

[Michael J. Spangler]

To an extent yes. You still need a conservative HP cavity geometry. Up to about 1400fps a shallow cup point penta will hold together. About 1150-1200fps is the limit for the bigger deeper pins and that's pushing it depending on the side wall profile.
These were 160gr out of a .40, ~1000 fps black, chrome ~1150

Gotcha. I think I need that 360-640 for my 38 special work. I like the idea of something that will expand a little more reliably in the snubby. I’m sure the 359-130 would be fine but I like a crimp groove of course.

Time to check MP website.

[Michael J. Spangler]

Ok I’m back on this kick.
KVO I’m judging by your measurements that this 360-640 might be too long for use in a 357 chambered 1873 rifle clone.

A 1.290” case with .345” gives me 1.635” which makes this whole thing moot if that’s the case.

Kind of disappointing. I wanted a new mould lol.
I guess I could load up some of the 359-130 nice and soft to see how they expand. If I like the results maybe I’ll get the 360-640L or if they’re a little too explosive I could get the 360-640 to balance out the weight and speed I can achieve with the snubby.

I’m glad I looked back here and did some reading before I bought anything.

By an my chance would you be able to confirm the OAL length in a 357 case?

[KVO]

Can't speak to an 1873 but they feed nice and slick through my Miroku 1892.

[Michael J. Spangler]

Can't speak to an 1873 but they feed nice and slick through my Miroku 1892.

Thank you very much. Yeah can’t really go over 1.590” or so if I remember correctly.
I know the Marlin will eat them but it’s not as pretty as the 73.

I guess I need to figure out if I want to get it or not. I would like to stick to one or two moulds for 38/357.
I mainly shoot 38. Probably 100:1 over 357. Maybe more. So I should be optimizing for that really and loading the 360-640 for the little bit of 357 I shoot.

[KVO]

I should have offered sooner but do you want some samples? PM me which molds as cast or coated, if you care what alloy etc and about how many.