More powder or shorter OAL?

djcantr · August 31, 2012, 12:57 PM

I'm finally starting to work up a major load for my G35. I'm using Titegroup, CCI small pistol primers and Montana Gold 180 grain JHPs. I seated a bullet to 1.17" and the bullet didn't contact rifling in the barrel. It seemed that 1.14" was about as long as I could go and not have them bind in the mags. I loaded up twenty rounds with 4.5 grain charges and 1.14" OAL and drove out and setup my chronograph. A ten round average was 904 fps. I want to get up to 925-930 fps so I can make major (917 fps) with a small amount of cushion. Would it be advisable to go to 4.6 grains and then 4.7 grains if necessary with 1.14" OAL or should I stick with 4.5 grains and try loading them to 1.13"? How much velocity might a .01" shorter OAL add? I'm concerned about pressure.

I guess my question here is which load would probably have the lowest pressure if both loads produced the same velocity? 1.13" with 4.5 grains or 1.14" with 4.7 grains?

oldpapps · August 31, 2012, 04:23 PM

Too deep for me. All I can do is guess.
More to the point, with the same velocities, the pressures would be, I think, very close to being the same. So, why be concerned. Now if you were working on a bench rail gun, maybe but then...

I would be more interested in making certain that the OAL is good for any and all weapons that I may want/need to use them in.
Many years-a-go, I loaded up some .357 Mags. They worked great in my S&W Model 19. BUT were too long for my S&W Model 27 and Model 28's cylinders. That could have been a bad surprise if I hadn't checked them.

I want to see what the internal ballistictisons (that's not how to spell that) say about your question.

Keep it safe,

OSOK

steve4102 · August 31, 2012, 04:41 PM

Be aware that TG is probably responsible for more KB in the 40 than all other powders combined. If you want higher velocities switch to a slower more forgiving powder.

**Unclenick** · August 31, 2012, 05:07 PM

Agree with going to a slower powder. Fast powders maximize pressure for the velocity delivered. But to answer your question on general principles, for a given velocity you want to use more powder rather than shorter COL if you want to minimize pressure needed to get there.

Nathan · August 31, 2012, 05:18 PM

Does this OAL feed? If so, maybe stay with it. If not, shorter feeds faster and longer feeds slower. Nominal to me is 1.125".

After picking an OAL which feeds with a mid charge weight, then I would split the range into like 5 loads and try them for accuracy. I test 40 at 15 yds.

Sorry, but answering your question really isn't possible by my way of thinking...

FWIW, I like Titegroup, Longshot and AA#5 in 40. AA#5 is probably my favorite, but Longshot is faster.

djcantr · August 31, 2012, 05:35 PM

Quote:

Originally Posted by oldpapps

Too deep for me. All I can do is guess.
More to the point, with the same velocities, the pressures would be, I think, very close to being the same. So, why be concerned. Now if you were working on a bench rail gun, maybe but then...

I would be more interested in making certain that the OAL is good for any and all weapons that I may want/need to use them in.
Many years-a-go, I loaded up some .357 Mags. They worked great in my S&W Model 19. BUT were too long for my S&W Model 27 and Model 28's cylinders. That could have been a bad surprise if I hadn't checked them.

I want to see what the internal ballistictisons (that's not how to spell that) say about your question.

Keep it safe,

OSOK

This pistol is the only one I have in .40 S&W. That leaves me pretty free to fine tune the load to this particular pistol. Thanks for your input!

BillM · August 31, 2012, 05:35 PM

Montana Golds will generally take .1-.2 gr more than othere bullets
to get to the same velocity. Might have something to do with that
shiny jacket material.

OAL. I load 1.140 in my G35, but with some bullets I have to go a bit
shorter to get them to feed reliably. I've gone as short as 1.060 on
some steep angled 180's, but that was on a minor load for Production.

Stock barrel? You are pushing it with the titegroup, but it should be
OK at 170 PF or so. Watch for pressure signs.

I've pretty much quit titegroup. Solo 1000 is softer and much cleaner, especially with lead bullets.

djcantr · August 31, 2012, 05:39 PM

Quote:

Originally Posted by steve4102

Be aware that TG is probably responsible for more KB in the 40 than all other powders combined. If you want higher velocities switch to a slower more forgiving powder.

Is it the actual powder that's responsible or poor loading practices? It's a dense powder so it doesn't fill the case as full as other powders and is very dark which can make it hard to see in the case. I see how that could make it easy for a distracted loader to double charge a case. It's my understanding that double charges are the reason for the KBs when using Titegroup. Do you know of other reasons?

djcantr · August 31, 2012, 05:42 PM

Quote:

Originally Posted by Unclenick

Agree with going to a slower powder. Fast powders maximize pressure for the velocity delivered. But to answer your question on general principles, for a given velocity you want to use more powder rather than shorter COL if you want to minimize pressure needed to get there.

I thought that the longer OAL would be the lowest pressure route to get to a specific velocity which is why I started much longer than the 1.125" in the load data I found. Thanks for confirming!

djcantr · August 31, 2012, 05:49 PM

Quote:

Originally Posted by Nathan

Does this OAL feed? If so, maybe stay with it. If not, shorter feeds faster and longer feeds slower. Nominal to me is 1.125".

After picking an OAL which feeds with a mid charge weight, then I would split the range into like 5 loads and try them for accuracy. I test 40 at 15 yds.

Sorry, but answering your question really isn't possible by my way of thinking...

FWIW, I like Titegroup, Longshot and AA#5 in 40. AA#5 is probably my favorite, but Longshot is faster.

That OAL fed fine, though I only fired 20 rounds so that's not really a very good sample size.

If I didn't care about power factor, I'd be working up this load like you would. I load other cartridges for general plinking and accuracy, but this load is so I can make major power factor in USPSA. Once I work this load up to 925-930 fps I'll test for accuracy and if it's not acceptable then, well, I'm not sure what I'll do. I suspect it will be accurate enough for what I want this load to do, though.

djcantr · August 31, 2012, 05:54 PM

Quote:

Originally Posted by BillM

Montana Golds will generally take .1-.2 gr more than othere bullets
to get to the same velocity. Might have something to do with that
shiny jacket material.

OAL. I load 1.140 in my G35, but with some bullets I have to go a bit
shorter to get them to feed reliably. I've gone as short as 1.060 on
some steep angled 180's, but that was on a minor load for Production.

Stock barrel? You are pushing it with the titegroup, but it should be
OK at 170 PF or so. Watch for pressure signs.

I've pretty much quit titegroup. Solo 1000 is softer and much cleaner, especially with lead bullets.

I'm running a stock barrel. I'm not wanting to go above 170 PF. 165-167 PF is fine for me. I just want to barely make major. I inspected the cases from today and didn't see any signs of over pressure.

steve4102 · August 31, 2012, 09:05 PM

Quote:

Is it the actual powder that's responsible or poor loading practices?

Both. TG has a very narrow window and does not play nice in the 40 when pushed to the upper limits. Its goes from safe to nasty very quickly.

Do the Google on 40 S&W and TG.

August 31, 2012, 12:57 PM	#1
djcantr Senior Member Join Date: January 28, 2012 Posts: 215	More powder or shorter OAL? I'm finally starting to work up a major load for my G35. I'm using Titegroup, CCI small pistol primers and Montana Gold 180 grain JHPs. I seated a bullet to 1.17" and the bullet didn't contact rifling in the barrel. It seemed that 1.14" was about as long as I could go and not have them bind in the mags. I loaded up twenty rounds with 4.5 grain charges and 1.14" OAL and drove out and setup my chronograph. A ten round average was 904 fps. I want to get up to 925-930 fps so I can make major (917 fps) with a small amount of cushion. Would it be advisable to go to 4.6 grains and then 4.7 grains if necessary with 1.14" OAL or should I stick with 4.5 grains and try loading them to 1.13"? How much velocity might a .01" shorter OAL add? I'm concerned about pressure. I guess my question here is which load would probably have the lowest pressure if both loads produced the same velocity? 1.13" with 4.5 grains or 1.14" with 4.7 grains?

August 31, 2012, 05:07 PM	#4
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Agree with going to a slower powder. Fast powders maximize pressure for the velocity delivered. But to answer your question on general principles, for a given velocity you want to use more powder rather than shorter COL if you want to minimize pressure needed to get there. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

August 31, 2012, 04:23 PM	#2
oldpapps Senior Member Join Date: September 22, 2011 Location: Middle America Posts: 518	Too deep for me. All I can do is guess. More to the point, with the same velocities, the pressures would be, I think, very close to being the same. So, why be concerned. Now if you were working on a bench rail gun, maybe but then... I would be more interested in making certain that the OAL is good for any and all weapons that I may want/need to use them in. Many years-a-go, I loaded up some .357 Mags. They worked great in my S&W Model 19. BUT were too long for my S&W Model 27 and Model 28's cylinders. That could have been a bad surprise if I hadn't checked them. I want to see what the internal ballistictisons (that's not how to spell that) say about your question. Keep it safe, OSOK

August 31, 2012, 04:41 PM	#3
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	Be aware that TG is probably responsible for more KB in the 40 than all other powders combined. If you want higher velocities switch to a slower more forgiving powder.

August 31, 2012, 05:18 PM	#5
Nathan Senior Member Join Date: July 1, 2001 Posts: 6,331	Does this OAL feed? If so, maybe stay with it. If not, shorter feeds faster and longer feeds slower. Nominal to me is 1.125". After picking an OAL which feeds with a mid charge weight, then I would split the range into like 5 loads and try them for accuracy. I test 40 at 15 yds. Sorry, but answering your question really isn't possible by my way of thinking... FWIW, I like Titegroup, Longshot and AA#5 in 40. AA#5 is probably my favorite, but Longshot is faster.

August 31, 2012, 05:35 PM	#7
BillM Senior Member Join Date: January 20, 2009 Location: Amity Oregon Posts: 791	Montana Golds will generally take .1-.2 gr more than othere bullets to get to the same velocity. Might have something to do with that shiny jacket material. OAL. I load 1.140 in my G35, but with some bullets I have to go a bit shorter to get them to feed reliably. I've gone as short as 1.060 on some steep angled 180's, but that was on a minor load for Production. Stock barrel? You are pushing it with the titegroup, but it should be OK at 170 PF or so. Watch for pressure signs. I've pretty much quit titegroup. Solo 1000 is softer and much cleaner, especially with lead bullets.