9mm +P loads

H

Howa 9700

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Recently picked up some 9mm bullets from Sierra and after seeing numerous variations in load data for them from variety of sources, decided to go straight to the source, so picked up a Sierrra Load Manual, sixth edition to see what they had to say about it.

Quickly discovered Sierra's manual has load data not found from any of my other sources. Load data like 6mm Rem Ackley Improved. Try finding that elsewhere.

But it also has a set of load data for 9mm +P for higher pressure loads for military rounds, service pistols, etc. The only place I've ever seen it. It appears that Sig and other also make factory ammo for +P designated guns, all coming with warning that pistol must be rated for such.

So first question is..........how does one know if your pistol is rated for +P ammo? Nothing in the owners manual or online sources say one way or the other.

Second question.......if pistol is rated for +P ammo, then it would appear to be safe to load to MAX loads in all the published load data intended for pistols that are not rated +P? In Sierra's load data, same everything for two otherwise identical loads has +P running about half a grain more than max loads not for +P.

Not seeking to blow anyone or anything up, just seeking clarification.
 
Howa 9700 said:
So first question is..........how does one know if your pistol is rated for +P ammo? Nothing in the owners manual or online sources say one way or the other.
Click to expand...
My Taurus G3C 9mm Luger has this in manual. Screenshot_20230614-150923_Drive.jpg

Check owners manuals from other make & model.

2nd question- Most handloaders dont have pressure testing equipment. Any change of componets, may change pressures. Chambers are not all the same. So, start low, work up.
 
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Western Data used to have +P data for 9mm.
(data is on Hodgdons site - they bought Western, select 9mm +P)

Most new 9mms are rated for +P ammo, but if in doubt I would contact the maker of the firearm in question.

Second question.......if pistol is rated for +P ammo, then it would appear to be safe to load to MAX loads in all the published load data intended for pistols that are not rated +P? In Sierra's load data, same everything for two otherwise identical loads has +P running about half a grain more than max loads not for +P.
Click to expand...

Well maybe....
The problem is the max loads listed may not be +P, but you don't have
the same lot of powder, primers, bullets, brass and barrel/gun that they used in testing,
so what was a MAX non +P load in their case might very well be +P with your lots of components in your firearm.
So really the thing to do is work up, and remember by the time you see pressure signs in 9mm you are WAY to high IMO.
Also small changes on OAL in 9mm can make a big difference, so if you have to load shorter than the listed OAL that will up pressure.
 
Pistol in question is a Sig p226, which I now see their FAQ says is ok for +P loads. Would like to think they share that somewhere else other than their website's FAQ.

Also find it odd that Sig would not include an owner's manual with a new gun. You want one you have to go to their website and print it yourself.

FAQ also mentions that use of any reloads will void the warranty. Hopefully warranty work won't be needed.
 
Google 9mm Major.

i own a Sig 320 X5 Legion and reloads or remanufactured ammo does not affect the warranty.
 
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Otto said:
i own a Sig 320 X5 Legion and reloads or remanufactured ammo does not affect the warranty.
Click to expand...

This limited warranty is null and void if the firearm has been misused, damaged (by accident or otherwise), fired with hand loaded, reloaded, or improper ammunition, fired with an obstruction in the barrel, damaged through failure to provide reasonable and necessary maintenance as described in the manual accompanying the firearm, or if unauthorized repair or any alteration, including of a cosmetic nature, has been performed on the firearm. Cerakote and other decorative finishes will not void your warranty if applied properly. Decorative finishes that are improperly applied to our products may cause failures and would not be covered under the Limited Lifetime Warranty. Any cosmetic damage to aftermarket finishes is not the responsibility of SIG SAUER. This limited warranty does not apply to normal wear and tear of any parts.

Directly quoted from the SIG Warranty page on their website....................
 
Howa 9700 said:
.......
.......

Second question.......if pistol is rated for +P ammo, then it would appear to be safe to load to MAX loads in all the published load data intended for pistols that are not rated +P? In Sierra's load data, same everything for two otherwise identical loads has +P running about half a grain more than max loads not for +P.

Not seeking to blow anyone or anything up, just seeking clarification.
Click to expand...

If a handgun is rated for +P ammo any published and tested load data for standard pressure ammo, even at the max, will be safe to shoot in any pistol in good operating condition.
 
Howa 9700 said:
9mm bullets from Sierra ... Sierrra Load Manual, sixth edition ... has ... load data for 9mm +P

if pistol is rated for +P ammo, then it would appear to be safe to load to MAX loads in all the published load data

Not seeking to blow anyone or anything up, just seeking clarification.
Click to expand...
SAFETY WARNING: While there are available +P load data, they were tested with NEW BRASS. If you are using MIXED RANGE BRASS with unknown reload history (With increasing prevalence of USPSA 9mm Major brass that are usually fired once and left for discard that tends to overly expand/bulge case base area of brass < Think "thinned" >), I would stick to mid to high range load data with careful powder work up towards near max load data.

I load max published load data preferably with known once-fired brass (Brass I saw go from factory box to pistol then range floor). While I have shot +P/+P+ 9mm ammunition out of my Glock 17, I do not reload at +P pressures with mixed range brass.

And even if you are using new brass, 9mm bullet diameter/case wall thickness can vary and I would test for neck tension so there is no bullet setback - https://www.thehighroad.org/index.p...neck-tension-and-bullet-setback.830072/page-4

Even several thousandths of bullet setback/deeper seating of bullet could increase chamber pressure by several thousand PSI - https://www.thehighroad.org/index.p...-and-discussions.778197/page-11#post-12503881

Be safe.

index.php
 
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Hodgdon/Western/Ramshot provides +P load data and compare the following sample 9mm normal pressure with +P load data along with highest listed velocity load for 115 gr Sierra FMJ - https://www.hodgdonreloading.com/reloading-data-center
  • 9mm 115 gr Sierra FMJ No. 5 COL 1.100" Start 5.3 gr (1,001 fps) 29,100 PSI - Max 6.3 gr (1,148 fps) 34,200 PSI
  • 9mm+P 115 gr Sierra FMJ No. 5 COL 1.100" Start 6.3 gr (1,155 fps) 36,100 PSI - Max 6.7 gr (1,219 fps) 38,400 PSI
  • 9mm +P 115 gr Sierra FMJ No. 7 COL 1.100" Start 7.8 gr (1,166 fps) 35,400 PSI - Max 8.5 gr (1,242 fps) 38,400 PSI

FYI, if you are looking for higher velocity loads, consider referencing Speer load data (Normal pressure loads) which are listed by highest velocity loads down to slower velocity loads - https://reloadingdata.speer.com/downloads/speer/reloading-pdfs/handgun/9mm_Luger__115_rev1.pdf
  • 9mm 115 gr Speer TMJ Blue Dot COL 1.135" Start 7.7 gr (1161 fps) - Max 8.5 gr (1258 fps)
  • 9mm 115 gr Speer TMJ Unique COL 1.135" Start 5.6 gr (1166 fps) - Max 6.3 gr (1244 fps)
  • 9mm 115 gr Speer TMJ BE86 COL 1.135" Start 5.4 gr (1136 fps) - Max 6.2 gr (1241 fps)
 
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