What is your favorite load for your PCC?

[nickbfishn]

20 minutes ago, KzBoost said:

Thanks for the info!

 

Any reason you're loading 1.120 and not longer? I was told to load as long as possible as long as it passes plunk test and feeds well.

I’ve had longer loads and kept having issues. So far with 1.12 I have not had a single feed problem. I’m sure I could go to 1.13 but I don’t really know why folks drag them out and load long, I just don’t really understand the science of it all. I just try things until I find what works. In my gun 1.12 is what works reliably. 

[nickbfishn]

9 hours ago, gerritm said:

For both of my PCC's. Taccom ULW with his light buffer and JP 14.5 barrel with pinned JP tactical comp with same Taccom ULW buffer. 

 

Steel load: 2.9grs Titegroup, 115gr SNS Casting RN, 1.12OAL Very soft, accurate, and reliable.

 

USPSA load: 3.1grs Titegroup, 147gr SNS Casting RN, 1.12OAL. Red dot bounces a little more in the Taccom, but super soft in the JP barrel.

 

gerritm

I forgot to add that I also have loaded some bayou 147 RN with very similar numbers

 

So in all I have:

 

Bayou 124 Rn (steel)

3.2 n320 *I might try 3.0/2.8

1.12

 

Bayou 124 RN (uspsa)

3.8 n320 

1.12

 

Bayou 147 RN (steel)

2.8 n320

1.12

 

Bayou 147 Rn (uspsa)

3.2 n320

1.12

 

I should be able to chrono all this week and report back with numbers. However, my main focus now is just a steel load so I can having a winning load for the AL state match in December 

[gerritm]

7 hours ago, KzBoost said:

Thanks for the info!

 

Any reason you're loading 1.120 and not longer? I was told to load as long as possible as long as it passes plunk test and feeds well.

We load for all our guns at 1.12OAL. Running Glock mags I have had some issues with the mags not liking the longer OAL. Not a problem in our 2011's. I know my JP barrel will plunk test up to 1.16 as I have checked my open loads in it. The Glock mags get finnicky over 1.13 or so. Especially when you are running extended basepads. Had an issue the other day with some practice rounds I loaded up for my 2011 @ 1.16 and was going to use them up. Loaded in the mag fine until they went into the Dawson basepad and jammed. Turned into a salt shaker.

 

gerritm

[littlefish]

1. 16" Faxon, no brake or comp, NFA upper/lower, JP SCS-bolt-trigger

2. 115gr JHP Rem, .355 

3. 4.0 HP-38 (chrono broke so not sure PF)

4. Various primers

5. ~1.110-1.115 OAL (runs extended Glock mags fine)

6. 99.99% at couple thousand rounds plus

7. Very tight at 17 yards off rest 

8. OK, probably could do better with more tuning or better shooter (I get pretty sloppy in hoser mode)

Edited October 31, 2017 by littlefish

[Tonka]

On ‎9‎/‎3‎/‎2017 at 12:28 AM, Hammer002 said:

Well, I think some people are going to freak out when I post it, but here we go...

 

1.  KG custom, 16", Hiperfire 24, Aimpoint Comp ML3 2 MOA,  BCM charging handle, Yankee Hill slant brake (for timer pick up)

2.  135gn Black Bullets International coated lead RN

3.  2.9 Clays (yes, that clays)

4.  Winchester

5.  1.120

6.  Not a malfunction with it yet.

7.  Doubles within an inch many times out to medium range and double A's on long targets are no issue at speed.  Excellent Steel Challenge load

8.  Very very soft. Very very quiet even with brake.  Sounds suppressed.  Have to be very attentive with timer.

9.  Haven't measured splits

10.  Minimal dot movement.  

 

FPS last tested was a surprising 1045.  The load came from pure experiment and purposely trying to put a load together that would be too soft and work up for steel challenge.  Wound up being perfect.  Clays for 9mm is unheard of so far as I know, but the pressure listings I did find were low for even a load with slightly more powder.  Seems the longer barrel is getting the velocity needed for power factor.  Also use WSf with great success, just up into the 145 range for power factor.

Yep clay is a nice powder have used it in 45 and 40 as well, just like the other shotgun powders.  I have also used WST for 9mm and that works well also

 

[stick]

1.       PSA 16” with Hiperfire 24C

2.       147gr Everglades RN

3.       Titegroup 2.5gr

4.       Federal

5.       1.135 oal

6.       No issues

7.       Very accurate even with my 6 moa dot

8.       Soft shooting.

9.       Haven’t measured

10.   Minimal dot movement

133 PF 

Edited November 7, 2017 by stick

[stick]

 

Tested some 160gr Bayou today

1. PSA 16" with hiperfire 24c
2. Bayou 160gr RN
3. Titegroup 2.5gr
4. Federal
5. 1.140 oal
6. no issues
7. decent accuracy
8. Snappy
9. haven't measured
10. minimal dot movement

144PF

I didn't like the load.  I thought it would be better than the 147gr rounds, but it wasn't.  the load was snappy and the felt recoil (for a 9mm) was more noticeable than the 147gr rounds.  I think the longer bullet profile creates more pressure than the smaller 147gr.

[Aircooled6racer]

Hello: I think your 147 load will be right at 125PF in my barrels, so that would be the difference with your 160 grain load. Thanks, Eric

[stick]

On ‎11‎/‎7‎/‎2017 at 5:55 PM, Aircooled6racer said:

Hello: I think your 147 load will be right at 125PF in my barrels, so that would be the difference with your 160 grain load. Thanks, Eric

I've heard a lot about the 160 gr load for PCC.  I decided to try it and see for my self.  I was looking for reduced dot movement and recoil control (not that the 9mm recoils) for faster follow up shots.

[jtrump]

GMR-13

 

115 PD JHP @ 1.140   with 4.3g Titegroup   135PF

 

115 Black Bullet @ 1.130  with 3.9g    AVG 1207,  139pf:::::     Backed it off to 3.8 running at 137PF nice and soft.

 

[bmiller]

On 11/7/2017 at 5:08 PM, stick said:

 

Tested some 160gr Bayou today

1. PSA 16" with hiperfire 24c
2. Bayou 160gr RN
3. Titegroup 2.5gr
4. Federal
5. 1.140 oal
6. no issues
7. decent accuracy
8. Snappy
9. haven't measured
10. minimal dot movement

144PF

I didn't like the load.  I thought it would be better than the 147gr rounds, but it wasn't.  the load was snappy and the felt recoil (for a 9mm) was more noticeable than the 147gr rounds.  I think the longer bullet profile creates more pressure than the smaller 147gr.

Be careful with the 160 grain bullets in 9mm.  I played with them a few years ago with solo1000.  I found a load that was extremely soft.  I can't remember the charge, but it was small.  Was around 135 pf in a 6" para.  The primers looked a little funny, so I gave a handful to a friend who had access to a ballistics lab.  Pressure was over 60000 psi at its peak. It had a wicked spike to it as well.  Needless to say,  the rest of the box went unused.  YRMV.

[Sarge]

1 hour ago, bmiller said:

Be careful with the 160 grain bullets in 9mm.  I played with them a few years ago with solo1000.  I found a load that was extremely soft.  I can't remember the charge, but it was small.  Was around 135 pf in a 6" para.  The primers looked a little funny, so I gave a handful to a friend who had access to a ballistics lab.  Pressure was over 60000 psi at its peak. It had a wicked spike to it as well.  Needless to say,  the rest of the box went unused.  YRMV.

I have been told more guns have been blown up by small charges than over charges. N310 with 147’s can sound and feel like a cap gun but have tremendous pressure spikes if just a little off.

[MikieM]

I wish you two boys would explain this phenomenon of a big bullet and a small powder charge, a little further.

[L9X25]

1 hour ago, Sarge said:

I have been told more guns have been blown up by small charges than over charges. N310 with 147’s can sound and feel like a cap gun but have tremendous pressure spikes if just a little off.

 

I was involved when shooting the 220gr lead projectiles in .40 cal limited pistols became the fad.  The huge projectile reduces the powder volume available in the case (as a 160gr does in a 9mm) and a small charge of fast powder is usually used to drive the projectile.  As was mentioned before, the huge projectile, along with the fast powder created a large pressure "spike" that blew out many .40 cal cases and led to end of that round's popularity.  I still have several boxes of those projectiles, along with loaded rounds that I am not willing to shoot and am too lazy to pull for the cases.  

 

I think the heavy bullet theory is more relevant to pistols, since they need to (violently) accelerate a light projectile to a high velocity within 5" to make power factor.  Going to a heavier bullet means that the velocity needed is lower and the acceleration does not have to be as violent.  With 14"+ of barrel available in a PCC, we can use a slower powder to accelerate a light bullet to minor velocity without the violence felt in the pistol.  That combined with the weight of the average PCC, negates much of the perceived advantage of the heavy bullet theory.

 

ETA: The science behind the heavy bullet theory is that, at 130pf, a 115gr projectile and a 160gr projectile have the same kinetic energy, and recoil with the same force, but it is the force over time that we perceive.  A 160 gr projectile's recoil impulse lasts 40% longer than a 115's and tends to feel more like a "push" than the "hit" of a 115.  The same amount of energy is spread over a longer period of time, the feel is not as abrupt.  Makes sense?

Edited November 10, 2017 by L9X25

[MikieM]

Well done, L9.

[stick]

12 hours ago, bmiller said:

Be careful with the 160 grain bullets in 9mm.  I played with them a few years ago with solo1000.  I found a load that was extremely soft.  I can't remember the charge, but it was small.  Was around 135 pf in a 6" para.  The primers looked a little funny, so I gave a handful to a friend who had access to a ballistics lab.  Pressure was over 60000 psi at its peak. It had a wicked spike to it as well.  Needless to say,  the rest of the box went unused.  YRMV.

I didn't like the 160gr load I worked.  They just didn't feel right (If that makes sense?) they seemed snappy.  I'm sticking with my 147gr load.

[mahamoti]

Finally got to a chrono.  JP 16” barrel, JP bolt, JP 9mm SCS (stock config), BCP Colt pattern lower.

 

124gr Precision Delta FMJ

CCI SPP500

1.16” OAL

3.4gr Titegroup =126pf

3.5gr = 132pf

 

Cycles 3.0gr at 109pf just fine, and still locks bolt back.

 

1.16” is super long, but the JP barrel and Metalform mags handle it with no problems, even the Taccom coupled mag feeds great.

Edited November 13, 2017 by mahamoti

[ChiefArmamentGroup]

L9, great explanation on the heavy for caliber theory. I think that is also why the Blitz buffer has been such a huge success. That theory is pretty much inverted for open guns. Light projectile/slow burning powder.

 

But it is very hard to develop a load that will work well in all guns, even within the same model of the firearm for that matter. For instance I have shot with Jtrump a lot. Great shooter and a good friend. We have literally taken taken the same loads and seen a 150 fps difference between two guns. Granted his JP has a 14.5" barrel (my 16" barrel will give a little bit extra oomph, but not THAT much). Even when tested with other 16" barrels I would see 40-60fps spreads in the two guns. Personally I love 147s in handguns and 115s in PCCs. Open guns are an entirely different breed as well. Haven't shot enough of them to really give my opinion. 

 

With that said, is everyone else also seeing slow JP barrels? Or is this more a one off thing? Curious to see what everyone says. 

 

Chris

[mahamoti]

45 minutes ago, ChiefArmamentGroup said:

With that said, is everyone else also seeing slow JP barrels? Or is this more a one off thing? Curious to see what everyone says. 

Difference in bolt/buffer weight and lock time, maybe?  I don't know the truth of it, but I've heard talk of some blowbacks starting to cycle before the bullet leaves the barrel, which would have to cause some loss of velocity.  Someone w/more knowledge of the forces and timeframes involved might be able to chime in on that, though.

[ChiefArmamentGroup]

Mahamoti, with Jtrump's rifle we both have the Blitz setup...same springs...same buffer. Only difference is the bolt weight. His doesn't have the mass whereas mine still does. When comparing the two 16" guns I literally swapped uppers. Granted there is a little bit of variance due to the two triggers (one a CMG and the HF 24c), but it shouldn't have caused a 40-60fps variance. To a numbers guy like myself I find it interesting. Somethings work great for certain people and some things don't. 

 

I love making machines work to their top potential, but in the end it comes down to the user of said machine 99.9% of the time. If not I'd just buy one of Rob Latham's guns and call it quits! 

 

Chris

[L9X25]

This is my hypothesis on the slow JP barrels ...

 

I had a been using a stock Clymer reamer on a gun that I built.  The neck of the chamber was too tight, so I was swaging and neck splitting a lot of brass on the first firing, but velocity was fantastic.  I had Clymer make me custom reamer with a .001" larger diameter neck at the end of the chamber.  That completely solved the split brass problem, but the velocity fell significantly.  I spoke an engineer from Vihtavuori and he explained that the initial pressure spike caused by forcing the projectile out of the case created the heat/pressure to get the large powder charge burning efficiently and completely.  By opening the chamber mouth, and eliminating the pressure spike, it effectively slowed the burn rate of the powder and made for a less efficient burn.

 

Everyone knows that JP throats their barrels farther than most others.  I can drop 1.165+ ammo in and it will spin freely.  Nothing that fits in the magazine will be too long for the JP chamber.  Because of the deep throat, I think that the initial pressure is reduced by pressure blowing past the projectile while it is in the transition area, before it engages the rifling and completely seals the bore.   I have one of the slowest JP barrels that I have seen data on, but otherwise it is accurate and a great barrel. For example, my barrel took 4.6 of TG to make 130pf with a 115FMJ at 1.150".  I was initially shocked by all the people making comparable velocity with about 1 gr less powder, but noticed that most of the other JP barrels were slower than the norm and closer to mine.    Maybe all of this is just a coincidence, but I don't think so.

Edited November 14, 2017 by L9X25

[ChiefArmamentGroup]

L9, that is crazy! It makes sense though. I thought the longer throats would have something to do it. I guess that is why I see a lot of guys running JP barrels also tend to use some sort of coated bullet...seeing as the obturate to the bore more efficiently. 

 

Chris

[jtrump]

On 11/13/2017 at 9:54 PM, L9X25 said:

I have one of the slowest JP barrels that I have seen data on, but otherwise it is accurate and a great barrel. For example, my barrel took 4.6 of TG to make 130pf with a 115FMJ at 1.150".  I was initially shocked by all the people making comparable velocity with about 1 gr less powder, but noticed that most of the other JP barrels were slower than the norm and closer to mine.    Maybe all of this is just a coincidence, but I don't think so.

 

L9,  I'm almost right there with you.   4.3g TG behind a 115PD @ 1.140 oal puts me at 136pf,    running 3.8g TG behind a poly 115 @ 1.130 puts me at 139pf.   I think the poly coated bullets came out to be just at 100fps faster and they were loaded shorter.

 

I do believe it also has something to do with the longer throats in the JP barrels I tried some dummy loads to 1.17 and I finally started to feel the rifling but just barely.

[MikieM]

Wouldn't a longer throat (free bore) cause an increased procession of pressure in front of the bullet that could necessitate a greater powder charge than would normally be required had the throat been shorter?

Ideally we would want about three to five thousandths of an inch of "jump" before the bullet bearing surface reaches the lands, for near optimal performance.

While I'm thinking on it, don't the Bench Rest guys like their bullets just touching the lands?

Edited November 16, 2017 by MikieM

[Old3GNR]

L9x25 and others, Interesting observations.  I'm trying a new 124 JHP load for my JP. ,  3.5 gr Titegroup ran 993 fps or 123 pf.  I ran the same load from the same batch at the same time through my HK VP9 and got  1008 fps and 125 pf.  Here's the interesting part.  I previously ran a 124  FMJRN  with the same charge through the JP and it ran 1086 fps with 135 pf.  Since I chronoed that load I had replaced one of the tungsten buffer weights with steel and dropped to the light recoil spring. For reference, the 124 JHP ran 940 with 3.2 gr Titegroup and 964 with 3.4 gr.