9mm jacketed vs plated pressures

[aguynamedbryan]

Hi all,

I'm having trouble grasping how pressures work between jacketed and plated bullets. Do jacketed bullets require more or less powder to create the same velocity and pressure of a plated bullet?

I'm about to reload some 9mm 115gr hdy xtp with CFE pistol, and the hodgdon site has 115 gr spr gdhp. As I understand it, the spr gdhp is a plated bullet and I'm wondering if I can use the same powder grain range shown with my xtp bullets?

Any info/knowledge you can pass along is really appreciated!

[kcstott]

Jacketed, Plated or hard lead cast will generally all use the same max powder charges. I say generally because there is always an exception.

In a standard handgun load (non magnum and Non +P or +P+) you can typically treat plated and hard cast the same as jacketed. I would advise that if you are approaching max charge to back the load off 1/2 grain for hard cast and maybe the same for plated. but I've never had an issue and I load my all my pistol loads on the hot side. and I cast my own too.

Lyman has a great section in their manual on cast bullets. and all the max powder charges are reduced slightly from a same weight jacketed bullet.

[aguynamedbryan]

Jacketed, Plated or hard lead cast will generally all use the same max powder charges. I say generally because there is always an exception.

In a standard handgun load (non magnum and Non +P or +P+) you can typically treat plated and hard cast the same as jacketed. I would advise that if you are approaching max charge to back the load off 1/2 grain for hard cast and maybe the same for plated. but I've never had an issue and I load my all my pistol loads on the hot side. and I cast my own too.

Lyman has a great section in their manual on cast bullets. and all the max powder charges are reduced slightly from a same weight jacketed bullet.

Thank you for the info and reassurance!

[mofo1111]

Hornady XTP and Speer Gold Dot Hollow Point are both jacketed bullets. Jacketed bullets will cause higher pressure because the jacket is harder to deform into the rifling(maybe causing slower velocities). Plated and lead usually have lower pressures with less resistance in rifling because they are softer. They may have higher velocities due to less friction resistance. You may need to buy a Hornady Reloading book to find XTP data.

I have a Lee Reloading book but does not have CFE with 115 grain XTP bullet. COAL is either 1.125" or 1.142" in manual. Just be very careful when interchanging bullets. Each bullet usually have different lengths that change the internal volume of cartridge, everything else being the same. If you guess(timate) in the wrong direction, you can create dangerous pressures in firearm. Consider ALL variables if you are making substitutions!

[kcstott]

Hornady XTP and Speer Gold Dot Hollow Point are both jacketed bullets. Jacketed bullets will cause higher pressure because the jacket is harder to deform into the rifling(maybe causing slower velocities). Plated and lead usually have lower pressures with less resistance in rifling because they are softer. They may have higher velocities due to less friction resistance. You may need to buy a Hornady Reloading book to find XTP data.

I have a Lee Reloading book but does not have CFE with 115 grain XTP bullet. COAL is either 1.125" or 1.142" in manual. Just be very careful when interchanging bullets. Each bullet usually have different lengths that change the internal volume of cartridge, everything else being the same. If you guess(timate) in the wrong direction, you can create dangerous pressures in firearm. Consider ALL variables if you are making substitutions!

That's just flat wrong. Cast and plated will cause a jump in pressure due what's called bumping up. It's the bullet expanding too much due to being too soft for the velocity you desire to drive it. The harder you push the cast/plated bullets the more they expand in the bore and grip the bore causing pressure spikes and leading. This is why is is very important to match the lead hardness with the velocity you desire to drive the bullet. If the bullets had less friction they would not go faster. they would actually go slower due to the easy of getting down the bore. it would take more powder to push them to the same velocity. go try this with moly or HBN coated bullets and you'll find that the coated bullets need more powder due to the reduced friction.

[mofo1111]

That's just flat wrong. Cast and plated will cause a jump in pressure due what's called bumping up. It's the bullet expanding too much due to being too soft for the velocity you desire to drive it. The harder you push the cast/plated bullets the more they expand in the bore and grip the bore causing pressure spikes and leading. This is why is is very important to match the lead hardness with the velocity you desire to drive the bullet. If the bullets had less friction they would not go faster. they would actually go slower due to the easy of getting down the bore. it would take more powder to push them to the same velocity. go try this with moly or HBN coated bullets and you'll find that the coated bullets need more powder due to the reduced friction.

I don't think that my statement is flat wrong. Please enlighten me with your source of information so I can increase my knowledge. A bullet, being lead, plated, jacketed, or moly coated cannot expand more than any other bullet. It can only expand to the size of the barrel, and no more.

There are many more variables to consider on pressure and velocities concerning ammo than the type of bullets being used. The overall length of the projectile and how deep it is seated is huge concerning pressure changes and velocities. More so than jacketed vs plated vs lead. The other BIG factor is powder charge weight of course. Some lead bullets have lube on them to further change results. It is easier to push a lead bullet through a barrel than pushing a jacketed one. You may get more friction with a pure (non-lubed) lead projectile than a lubed lead bullet. It is harder to "engrave" the rifling into copper jacketed bullet than to "engrave" rifling into a lead or plated bullet. There is just too many variables changing the outcome of pressure and velocities within different bullets. Maybe it would be easier to compare if the bullet, primer, powder, powder charge weight, case, and seating depth was all the same. It would be nice to have a scientific test to read and examine. I haven't found one.

If I compare load data with similar bullet weight, the results are not crystal clear.

Let's take 9mm 115 grain bullet MAX load data as an example. (all from same reloading manual, not cherry picked. I wish I could compare apples to apples but COALs are different, and who knows if all bullets are the same.

Jacketed bullet
Silhouette 5.7 grains, COAL 1.100", 1161 FPS, 33912 PSI
AA #2 4.5 grains, COAL 1.077", 1057 FPS, 33567 PSI
AA #5 6.3 grains, COAL 1.077", 1137 FPS, 34913 PSI
AA #7 7.5 grains, COAL 1.077", 1127 FPS, 33684 PSI
True Blue 5.7 grains, COAL 1.077", 1120 FPS, 33919 PSI
Solo 1000 4.5 grains, COAL 1.077", 1052 FPS, 34667 PSI
Ram Zip 4.3 grains, COAL 1.077", 1048 FPS, 32916 PSI
R Competition 3.6 grains, COAL 1.077", 992 FPS, 34774 PSI
A Nitro 100 3.3 grains, COAL 1.100", 986 FPS, 33912 PSI

Lead bullet
Silhouette 5.7 grains, COAL 1.070", 1191 FPS, 34718 PSI (SEATED 0.030" DEEPER THAN JACKETED ABOVE, 30 FPS FASTER, 806 PSI HIGHER THAN JACKETED ABOVE)
AA #2 4.4 grains, COAL 1.070", 1109 FPS, 34808 PSI (0.1 GRAIN LESS POWDER, SEATED 0.007 DEEPER THAN , 52 FPS FASTER, 1241 PSI HIGHER THAN JACKET ABOVE)
AA #5 6.1 grains, COAL 1.070", 1179 FPS, 34420 PSI (0.2 LESS GRAINS, SEATED 0.007" DEEPER THAN, 42 FPS FASTER, 493 LESS PSI THAN JACKETED ABOVE)
AA #7 7.5 grains, COAL 1.070", 1178 FPS, 33632 PSI (SEATED 0.007" DEEPER THAN JACKETED ABOVE)(HIGHER FPS AND LOWER PSI THAN JACKETED ABOVE)
True Blue 5.6 grains, COAL 1.070", 1166 FPS, 34161 PSI (SEATED 0.007" DEEPER THAN JACKETED ABOVE, 0.1 LESS GRAINS, 46 FPS FASTER, HIGHER PSI)
Solo 1000 4.4 grains, COAL 1.070", 1110 FPS, 34167 PSI (0.1 LESS GRAINS POWDER, SEATED 0.007" DEEPER, 58 FPS FASTER, 500 PSI LOWER THAN JACKETED ABOVE)
Ram Zip 4.2 grains, COAL 1.070", 1117 FPS, 33842 PSI (0.1 LESS POWDER, SEATED 0.007" DEEPER, 69 FPS FASTER, 926 PSI HIGHER THAN JACKETED ABOVE)
R Competition 3.8 grains, COAL 1.070", 1084 FPS, 34622 PSI (0.2 GRAINS MORE POWDER, SEATED 0.007" DEEPER, 92 FPS FASTER, 152 PSI LESS THAN JACKETED ABOVE)
A Nitro 100 3.3 grains, COAL 1.070", 1032 FPS, 34451 PSI (SAME POWDER CHARGE, SEATED 0.03" DEEPER, 46 FPS FASTER, 530 PSI HIGHER)


Copper plated
Silhouette 5.9 grains COAL 1.140", 1163 FPS, 34061 PSI (0.2 MORE POWDER, SEATED 0.40" LESS THAN JACKED ABOVE, 2 FPS FASTER, 149 PSI HIGHER)
AA #2 4.6 grains, COAL 1.140", 1081 FPS, 33695 PSI (0.1 MORE GRAINS, 24 FPS FASTER, 128 PSI HIGHER)
AA #5 5.9 grains, COAL 1.140", 1150 FPS, 33854 PSI (0.4 LESS GRAINS, SEATED 0.063 LONGER THAN, VELOCITY 13 FPS FASTER, 1059 LESS PSI THAN JACKETED ABOVE)
AA #7 6.7 grains, COAL 1.140", 1165 FPS, NA PSI (LESS POWDER, SEATED 0.063 LONGER, VELOCITY FASTER, NO PSI TO COMPARE)
True Blue 5.8 grains, COAL 1.140", 1187 FPS, 34793 PSI (0.1 GRAIN MORE POWDER, 67 FPS FASTER, SEATED 0.063" LONGER, HIGHER PSI THAN JACKETED)
Solo 1000 4.3 grains, COAL 1.140", 1052 FPS, 34327 PSI (0.2 GRAINS LESS POWDER, SEATED 0.063" LONGER, SAME FPS, 340 LESS PSI THAN JACKETED ABOVE)
Ram Zip 4.6 grains, COAL 1.130", 1089 FPS, 34219 PSI (0.3 MORE POWDER, SEATED 0.053" LONGER, 41 FPS FASTER, 1303 PSI HIGHER)
R Competition 3.6 grains, COAL 1.140", 1003 FPS, 34202 PSI (SAME POWDER WEIGHT, SEATED 0.063" LONGER, 11 FPS FASTER, 572 LESS PSI)
A Nitro 100 3.5 grains, COAL 1.130", 990 FPS, 33000 PSI (0.2 GRAINS MORE POWDER, SEATED 0.03 LONGER, 4 FPS FASTER, 912 LESS PSI THAN JACKETED ABOVE)

Now that I look at the data, I may not be correct. If you look at the data at a glance, it may show that you are correct. But if you look deeper, the data is inconclusive. Like I stated above, there are many variables to consider. Lead vs jacketed vs plated seems trivial. The data above shows that powder charge and seating depth make more of a difference than anything else.

To say that my original post is false, may be a stretch. Without providing source material to prove your point, I cannot learn. Once again, please provide more info so that we can all learn. Thats what these forums should be for.

That's why I provided information. I provided it to learn and review data.
Cheers!

[kcstott]

I don't think that my statement is flat wrong. Please enlighten me with your source of information so I can increase my knowledge. A bullet, being lead, plated, jacketed, or moly coated cannot expand more than any other bullet. It can only expand to the size of the barrel, and no more.

There are many more variables to consider on pressure and velocities concerning ammo than the type of bullets being used. The overall length of the projectile and how deep it is seated is huge concerning pressure changes and velocities. More so than jacketed vs plated vs lead. The other BIG factor is powder charge weight of course. Some lead bullets have lube on them to further change results. It is easier to push a lead bullet through a barrel than pushing a jacketed one. You may get more friction with a pure (non-lubed) lead projectile than a lubed lead bullet. It is harder to "engrave" the rifling into copper jacketed bullet than to "engrave" rifling into a lead or plated bullet. There is just too many variables changing the outcome of pressure and velocities within different bullets. Maybe it would be easier to compare if the bullet, primer, powder, powder charge weight, case, and seating depth was all the same. It would be nice to have a scientific test to read and examine. I haven't found one.

If I compare load data with similar bullet weight, the results are not crystal clear.

Let's take 9mm 115 grain bullet MAX load data as an example. (all from same reloading manual, not cherry picked. I wish I could compare apples to apples but COALs are different, and who knows if all bullets are the same.

Jacketed bullet
Silhouette 5.7 grains, COAL 1.100", 1161 FPS, 33912 PSI
AA #2 4.5 grains, COAL 1.077", 1057 FPS, 33567 PSI
AA #5 6.3 grains, COAL 1.077", 1137 FPS, 34913 PSI
AA #7 7.5 grains, COAL 1.077", 1127 FPS, 33684 PSI
True Blue 5.7 grains, COAL 1.077", 1120 FPS, 33919 PSI
Solo 1000 4.5 grains, COAL 1.077", 1052 FPS, 34667 PSI
Ram Zip 4.3 grains, COAL 1.077", 1048 FPS, 32916 PSI
R Competition 3.6 grains, COAL 1.077", 992 FPS, 34774 PSI
A Nitro 100 3.3 grains, COAL 1.100", 986 FPS, 33912 PSI

Lead bullet
Silhouette 5.7 grains, COAL 1.070", 1191 FPS, 34718 PSI (SEATED 0.030" DEEPER THAN JACKETED ABOVE, 30 FPS FASTER, 806 PSI HIGHER THAN JACKETED ABOVE)
AA #2 4.4 grains, COAL 1.070", 1109 FPS, 34808 PSI (0.1 GRAIN LESS POWDER, SEATED 0.007 DEEPER THAN , 52 FPS FASTER, 1241 PSI HIGHER THAN JACKET ABOVE)
AA #5 6.1 grains, COAL 1.070", 1179 FPS, 34420 PSI (0.2 LESS GRAINS, SEATED 0.007" DEEPER THAN, 42 FPS FASTER, 493 LESS PSI THAN JACKETED ABOVE)
AA #7 7.5 grains, COAL 1.070", 1178 FPS, 33632 PSI (SEATED 0.007" DEEPER THAN JACKETED ABOVE)(HIGHER FPS AND LOWER PSI THAN JACKETED ABOVE)
True Blue 5.6 grains, COAL 1.070", 1166 FPS, 34161 PSI (SEATED 0.007" DEEPER THAN JACKETED ABOVE, 0.1 LESS GRAINS, 46 FPS FASTER, HIGHER PSI)
Solo 1000 4.4 grains, COAL 1.070", 1110 FPS, 34167 PSI (0.1 LESS GRAINS POWDER, SEATED 0.007" DEEPER, 58 FPS FASTER, 500 PSI LOWER THAN JACKETED ABOVE)
Ram Zip 4.2 grains, COAL 1.070", 1117 FPS, 33842 PSI (0.1 LESS POWDER, SEATED 0.007" DEEPER, 69 FPS FASTER, 926 PSI HIGHER THAN JACKETED ABOVE)
R Competition 3.8 grains, COAL 1.070", 1084 FPS, 34622 PSI (0.2 GRAINS MORE POWDER, SEATED 0.007" DEEPER, 92 FPS FASTER, 152 PSI LESS THAN JACKETED ABOVE)
A Nitro 100 3.3 grains, COAL 1.070", 1032 FPS, 34451 PSI (SAME POWDER CHARGE, SEATED 0.03" DEEPER, 46 FPS FASTER, 530 PSI HIGHER)


Copper plated
Silhouette 5.9 grains COAL 1.140", 1163 FPS, 34061 PSI (0.2 MORE POWDER, SEATED 0.40" LESS THAN JACKED ABOVE, 2 FPS FASTER, 149 PSI HIGHER)
AA #2 4.6 grains, COAL 1.140", 1081 FPS, 33695 PSI (0.1 MORE GRAINS, 24 FPS FASTER, 128 PSI HIGHER)
AA #5 5.9 grains, COAL 1.140", 1150 FPS, 33854 PSI (0.4 LESS GRAINS, SEATED 0.063 LONGER THAN, VELOCITY 13 FPS FASTER, 1059 LESS PSI THAN JACKETED ABOVE)
AA #7 6.7 grains, COAL 1.140", 1165 FPS, NA PSI (LESS POWDER, SEATED 0.063 LONGER, VELOCITY FASTER, NO PSI TO COMPARE)
True Blue 5.8 grains, COAL 1.140", 1187 FPS, 34793 PSI (0.1 GRAIN MORE POWDER, 67 FPS FASTER, SEATED 0.063" LONGER, HIGHER PSI THAN JACKETED)
Solo 1000 4.3 grains, COAL 1.140", 1052 FPS, 34327 PSI (0.2 GRAINS LESS POWDER, SEATED 0.063" LONGER, SAME FPS, 340 LESS PSI THAN JACKETED ABOVE)
Ram Zip 4.6 grains, COAL 1.130", 1089 FPS, 34219 PSI (0.3 MORE POWDER, SEATED 0.053" LONGER, 41 FPS FASTER, 1303 PSI HIGHER)
R Competition 3.6 grains, COAL 1.140", 1003 FPS, 34202 PSI (SAME POWDER WEIGHT, SEATED 0.063" LONGER, 11 FPS FASTER, 572 LESS PSI)
A Nitro 100 3.5 grains, COAL 1.130", 990 FPS, 33000 PSI (0.2 GRAINS MORE POWDER, SEATED 0.03 LONGER, 4 FPS FASTER, 912 LESS PSI THAN JACKETED ABOVE)

Now that I look at the data, I may not be correct. If you look at the data at a glance, it may show that you are correct. But if you look deeper, the data is inconclusive. Like I stated above, there are many variables to consider. Lead vs jacketed vs plated seems trivial. The data above shows that powder charge and seating depth make more of a difference than anything else.

To say that my original post is false, may be a stretch. Without providing source material to prove your point, I cannot learn. Once again, please provide more info so that we can all learn. Thats what these forums should be for.

That's why I provided information. I provided it to learn and review data.
Cheers!

for one you can't split hairs like that. Saami and CIP both disregard any PSI below 1000 as noise. They round data to the nearest 1KPSI so the data you sight is as you said inconclusive.

Now as to your statement that a bullet can only expand to the size of the barrel is correct but how much outward pressure is the bullet putting on the inside of the barrel? You see a bullet may expand only up to the diameter of the barrel but did it put more pressure on the barrel when it's fully expanded?

Not to mention you totally disregard bearing surface. By your statement a pure lead bullet should achieve the highest velocity for a given bullet weight at a given powder charge. How can that be true if the entire bullet slumps to fill in every possible area of barrel and deforms to the point that is now looks like a full wad cutter?

What I'm getting at here is there is a reason lead bullets at some point have to be gas checked. At some point no matter how hard the lead is it will slump. Gliding metal can only upset so far at the pressures we are talking about where as your typical lead alloy will start to slump and increase bearing surface and friction and lead the barrel.

All that said and I'll say it again for the most commonly loaded non magnum non +P, or +P+ pistol cartridges with velocities below 1200 fps i.e. .380 acp, 9mm, .40 S&W, 45 ACP, & 45 colt, you can treat cast or plated the same as jacketed.

I implore you to go get a copy of the Franklin Mann's book "The bullets flight, from powder to target. Lots of good test data in there. granted it's all black powder and lead cast stuff but it's the foundation of study on which all cast bullet technology is based.

[Sandspider500]

With pistol rounds lead bullets will typically run higher velocities at the same pressure as jacketeted bullets of the same weight, and use less powder to get to that velocity. That's why a chronograph is important when working up max loads. Don't try and chase lead bullet velocities with your jacketed loads for pistol. For straight wall pistol loads, case capacity is one of the important factors. Meaning your seating depth is important.

For an example, 38 special in Lyman 50th.

4" test barrel
1st a 158gr xtp load
158gr xtp(bullet is .675 long) 1.480 OAL
Start 4.7gr unique 675fps at 14,400 cup
Max 5gr unique 710 fps at 16,600 cup

2nd load a Lyman 358156 155gr swc
358156 155gr (my example measures.675 long without gascheck)
1.460 OAL
Start 3.4gr unique 601fps at 8,900 cup
Max 5.1gr unique 895fps at 16,100 cup
For what reason I dunno but Lyman lists the 358156 as cast with linotype, that's a bit hard for 16,000 cup. A softer alloy would not doubt be heavier and achieve that velocity with a lesser charge.

So if you were loading an xtp using the Lyman 358156 data and were using a chronograph trying to get to around 895fps, you'd be way over what you thought pressure wise.


As far as the 115 xtp and the 115 gdhp they're very similar and almost the exact same length. Hornady lists the 115gr xtp at 1.075 OAL and cfe starts at 4.7gr for 1000fps and a max of 5.8gr for 1200fps. Hornady doesn't list pressure but that's probably close to saami max. The hodgdon data and the speer load data load the gd to a longer OAL, that could be due to the ogive, I don't know, but probably why the hodgdon data goes to around 32,000 psi. You may not be able to load the xtp that long or maybe you can.

I also think that you can buy Hornady data for each cartridge for like $1. So there's that too.

[BrassCase]

Hi all,

I'm having trouble grasping how pressures work between jacketed and plated bullets. Do jacketed bullets require more or less powder to create the same velocity and pressure of a plated bullet?

I'm about to reload some 9mm 115gr hdy xtp with CFE pistol, and the hodgdon site has 115 gr spr gdhp. As I understand it, the spr gdhp is a plated bullet and I'm wondering if I can use the same powder grain range shown with my xtp bullets?

Any info/knowledge you can pass along is really appreciated!

I reload some 9mm with with HAP bullets, 115g, .355", COL 1.075, using CFE. 4.5 g will get me about 1040 fps. The Hornady Action Pistol bullet is basically an XTP without cuts in the cone. This is from the Hornady book.

[ar15barrels]

Hi all,

I'm having trouble grasping how pressures work between jacketed and plated bullets. Do jacketed bullets require more or less powder to create the same velocity and pressure of a plated bullet?

I'm about to reload some 9mm 115gr hdy xtp with CFE pistol, and the hodgdon site has 115 gr spr gdhp. As I understand it, the spr gdhp is a plated bullet and I'm wondering if I can use the same powder grain range shown with my xtp bullets?

Any info/knowledge you can pass along is really appreciated!

Here are two quickload simulations with the same charge weight, bullet weight, bullet length and overall loaded length.
The only difference is the bullet construction.

Cartridge          : 9 mm Luger (SAAMI)
Bullet             : .355, 124, Speer TMJ 3993
Useable Case Capaci: 7.552 grain H2O = 0.490 cm?
Cartridge O.A.L. L6: 1.100 inch = 27.94 mm
Barrel Length      : 5.0 inch = 127.0 mm
Powder             : Hodgdon Universal

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

+00.0  101     4.50   1168     376   34106   3136    100.0    0.512  ! Near Maximum !

Cartridge          : 9 mm Luger (SAAMI)
Bullet             : .355, 124, RN Rainier 9mm
Useable Case Capaci: 7.601 grain H2O = 0.494 cm?
Cartridge O.A.L. L6: 1.100 inch = 27.94 mm
Barrel Length      : 5.0 inch = 127.0 mm
Powder             : Hodgdon Universal

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

+00.0  100     4.50   1160     371   32162   3164    100.0    0.518  ! Near Maximum !

Bullet length and it's effect on seating depth will make a MUCH bigger difference in your charge weight, velocity and pressure than the bullet construction.

For example, here is a longer bullet of the same weight as above seated to the same overall cartridge length:

Cartridge          : 9 mm Luger (SAAMI)
Bullet             : .355, 124, Hornady FMJ/RN ENC 35577
Useable Case Capaci: 6.921 grain H2O = 0.449 cm?
Cartridge O.A.L. L6: 1.100 inch = 27.94 mm
Barrel Length      : 5.0 inch = 127.0 mm
Powder             : Hodgdon Universal

Step    Fill. Charge   Vel.  Energy   Pmax   Pmuz  Prop.Burnt B_Time
 %       %    Grains   fps   ft.lbs    psi    psi      %        ms

+00.0  110     4.50   1192     391   38868   3043    100.0    0.488  !DANGEROUS LOAD-DO NOT USE!