First Shots KKM 13 Twist Barrel

First topic message reminder :

This morning I fired frame mounted Caspian 1911 with 13 twist barrel. I shot 3.7 BE 185, 3.4 BE 185 and 3.5 BE Brazos 160. Everything shot on call. 3.4 shot very forgiving at 50 yards. The 160 and 185 recoil felt identical. Target is 3.4 load. Using 10# recoil spring. I'm going to load up some softer loads and see how it shoots. I'm a slide mount guy, so this feels funny to me. Recovery is lightning fast. I've hardly been shooting but shook them in pretty good today.
I shot 95 & 96 SF, then 40 shots TF all clean. Best target 100-8x.
Looking forward to reduced loads next time out. Will be RR'ing in near future.
I think the faster twist really helped the 3.4 loads stabilize for 50 yds. In the past with 16 twist barrels its not very forgiving. Jerry Keefer was running 3.0 BE. Next time out I will try the same.
Jon

I'm with you on the need for lighter recoil. I had injuries as well and had to make changes. I had pretty much settled on 3.5 BE with either 200 swc or 180 flat base both of the h&g 68 design. But I also had successfully used 3.3 but I lacked confidence in it. I also acquired an 8 cavity #130 mould but I didn't have initial success with loading for it. It also tended to have heavier recoil. As to the 160s l am around 3.9 BE for minimum that functions ( with my buns as they are now 10# spring etc)

I think Ladies technique is worth study, l know they don't crush the grips and they beat me handily with a 45. They have better balance and fine motor control ( read trigger)

But l am drifting from the thread topic...

BTW , why would a 1:13 barrel require a different expander?

Richard,

Premise is the same that made you using Colt sizing die, - elimination of swagging of the flat base bullets in the area close to the base.  I have no personal experience loading 45 Colt and using sizing dies designed / machined for this caliber for sizing 45 ACP / Match caliber.  Thus I use SAAMI drawings / specs to determine such usability.  SAAMI specs raise alarm for me: 45 Colt cases are specked to be cylindrical at 0.480" OD and bullet is specked to be 0.456".  45 ACP / Match cases are 0.473" at the top and bullets are 0.452"/0.453".  Since dies are machined for particular caliber, I'm apprehensive to use something that is designed to size case with +0.007" tolerance and in addition to that use bullet with -0.003" tolerance.  Cumulative error is in 0.01" or more area, and that spells trouble for me.  Example of such are trouble is bullet's set back.  There is no amount of crimp that can hold bullet by itself.  Especially lead / coated one, because brass is harder than lead.  Sooner or later ..............

So, it is not specific to 1:13 barrel, but rather process of figuring out why certain bullets create leading problem in such while there is no leading issue with same bullets in 1:16 barrels.  Obviously there might be other reasons, and I'm interested to learn what those might be.

AP

Loose grip only works sometimes…..much harder to be consistent. Firm grip is the only way to shoot the long line, short line is more forgiving. Older hands need to learn how to grip using the whole hand. When I was young I could grip just the front strap and back strap as I was taught. Now because of arthritis and injuries I use my entire hand and fingers to grip and the pistol stays in place. It took 6 hard months of training to get used to gripping like that. 50 yd fliers disappeared after getting new gripping method ironed out.
My 13 twist pistol is very forgiving to shoot. I loaned it to a friend for Cardinal/CMP/Perry ( not sure if he shot all 3). He shared without me asking that it was forgiving to shoot. 
I think barrel time is overrated except when comparing 5” vs. 6” barrel lengths. The longer barrels are harder to shoot well on the long line. These slow velocity rounds are not hard to shoot the long line. Shooting light slow loads in a 16 twist barrel will eat your lunch.
Southern Kommiefornia sucks, no matches since Mar 2020. So I haven’t been able to shoot a real match with it. I fought getting the trigger EXACTlY the way I wanted it. 3 hammers and 5 sears later I love it. Yeah I’m that picky. The pistol is one of my favorites now. I kinda feel like I’m cheating when I shooter it sometimes;)
Jon

PhotoEscape wrote:

BTW , why would a 1:13 barrel require a different expander?

Richard,

Premise is the same that made you using Colt sizing die, - elimination of swagging of the flat base bullets in the area close to the base.  I have no personal experience loading 45 Colt and using sizing dies designed / machined for this caliber for sizing 45 ACP / Match caliber.  Thus I use SAAMI drawings / specs to determine such usability.  SAAMI specs raise alarm for me: 45 Colt cases are specked to be cylindrical at 0.480" OD and bullet is specked to be 0.456".  45 ACP / Match cases are 0.473" at the top and bullets are 0.452"/0.453".  Since dies are machined for particular caliber, I'm apprehensive to use something that is designed to size case with +0.007" tolerance and in addition to that use bullet with -0.003" tolerance.  Cumulative error is in 0.01" or more area, and that spells trouble for me.  Example of such are trouble is bullet's set back.  There is no amount of crimp that can hold bullet by itself.  Especially lead / coated one, because brass is harder than lead.  Sooner or later ..............

So, it is not specific to 1:13 barrel, but rather process of figuring out why certain bullets create leading problem in such while there is no leading issue with same bullets in 1:16 barrels.  Obviously there might be other reasons, and I'm interested to learn what those might be.

AP

I haven't measured /tested/ researched the LC dies , I can only state that I can't insert either a lead or jacketed bullet into a case so sized until it's expanded. I've never had a bullet push back during feeding. The only downside I've seen is possibly a little more sensitvity to a dirty chamber. RE: leading , my earlier comments were in reference to a 1:16 Kart barrel , the 1:13 KKM has shown no sign of leading at all. However, so far I've only been running relatively low #s of rounds through in testing

RE: leading , my earlier comments were in reference to a 1:16 Kart barrel , the 1:13 KKM has shown no sign of leading at all. However, so far I've only been running relatively low #s of rounds through in testing

My interest in leading is specific to KKM 1:13 barrels.

As for sizing with 45LC sizing die - the fact of not being able to insert bullet at the top of the case might not be such below seating depth.  However as i stated, I have no practical experience of loading this caliber.

AP

Jerry Keefer recommended expanding such that the bullet can be hand seated to about 1/16". That has worked well for me. Older 45 Colt dies will work but be aware the SAAMI spec changed and most are now sizing the same as 45 ACP dies. I found Hornady 454 Casull dies to be perfect.

I have some fired brass that won't take a jacketed bullet. Crimp remnants perhaps? Havent tried to measure anything yet. 70's WCC fired 6x according to the friend that loaded it.

I got a 454 die from RCBS. I still feel resistance with the HTC expander. Not sized, 452 bullets were seating really easy in my WW brass.

My only LC die is steel. Typical taper to a cylindrical section for the 'neck, so it won't touch an ACP case.

Jon Eulette wrote:Loose grip only works sometimes…..much harder to be consistent. Firm grip is the only way to shoot the long line, short line is more forgiving. Older hands need to learn how to grip using the whole hand. When I was young I could grip just the front strap and back strap as I was taught. Now because of arthritis and injuries I use my entire hand and fingers to grip and the pistol stays in place. It took 6 hard months of training to get used to gripping like that. 50 yd fliers disappeared after getting new gripping method ironed out.
My 13 twist pistol is very forgiving to shoot. I loaned it to a friend for Cardinal/CMP/Perry ( not sure if he shot all 3). He shared without me asking that it was forgiving to shoot. 
I think barrel time is overrated except when comparing 5” vs. 6” barrel lengths. The longer barrels are harder to shoot well on the long line. These slow velocity rounds are not hard to shoot the long line. Shooting light slow loads in a 16 twist barrel will eat your lunch.
Southern Kommiefornia sucks, no matches since Mar 2020. So I haven’t been able to shoot a real match with it. I fought getting the trigger EXACTlY the way I wanted it. 3 hammers and 5 sears later I love it. Yeah I’m that picky. The pistol is one of my favorites now. I kinda feel like I’m cheating when I shooter it sometimes;)
Jon

I feel like this deserves a separate thread so as not to detract from the 1:13 subject which seems to have really struck a chord. If I understand what you're saying , using all three lower fingers , wrapped around the grip like you're holding a baseball bat ,using(to pull a # out of the air) 75% grip strength , you'll have much better control than squeezing the middle and ring fingers to 90% ,straight back. I assume the thumb is out of the picture with either method. Doing this seems to lessen the strain on the forearm at the same time. It sort of feels like the way I end up gripping a revolver to stop it from moving in my hand while cocking. Am I on the right track , and how do we move this thread over to Fundamentals if anyone's interested?

Agree with Jon shooting lite slow loads in a 1:16 did eat my lunch. It was a hard and time consuming lesson to learn. 

As I have become older, I have also modified my grip to use my entire hand with what I would characterize as a medium grip pressure. Doing this is keeping me competitive and strangely feels correct as the gun/hand/fingers pressure difference feels uniform and disappears.

I also agree with Bruce on sizing. For lead, I have used a Redding 45 Colt sizing die for many years. I found the 45 ACP sizing dies with the standard Dillon expander to pressure compress the lead bullet when seating and 50 yard accuracy suffered. I have tested many different crimps with the Zero 185 HPWSC for 50 yard accuracy. A .469 crimp and 4.05gns BE seems to provide the best overall accuracy from the Kart barrel in my gun. 

For the past few years I have been trying to reduce recoil for the short line and the minimum load my gun with a frame mount dot would reliably operate on was  3.0 BE and a 10# recoil spring with the Zero bullet mentioned above. This load ate my lunch at the short line as the energy, recoil and recovery seemed completely wrong. My scores suffered and cost me a few matches i would have liked to won. SO recently i have been working on the minimum load that feels correct for the short line and I have settled for 3.3 gns BE and a 16# recoil spring. This works very well and feels correct for both the short line with 3.3 and 4.05 BE for the long line.  

So, i am interested in the KKM 1:13 for reduced recoil, but after my experience I am skeptical but hopeful.

Yeah, and as my friends said to me The bullet has to go through the paper!

bruce martindale wrote:Yeah, and as my friends said to me The bullet has to go through the paper!

UPDATE: Last weekend ,four of us got together to try various loads in my 1:13 ball gun. Shooters ranged in age from mid 50s to early 70s , classifications ranging from Expert to Master. This was the first time the other 3 shooters tried this gun. One shooter fired a magazine of 2.8 BE and 200 LSWC and was convinced , another laughed out loud after one 3.6 WST and a Zero 185JHP, the remaining shooter was pleased with 3.3 of BE with a Brazo 160LSWC. After a number of jokes about sourcing recoil springs out of old Bic pens , and having to wear a skirt when shooting these loads , I believe all 3 shooters are about to get guns rebarreled with KKM 1:13 barrels. Unfortunately , I was able to obtain the same recoil reduction with 200gr jacketed bullets , vs 185JHP , as was evident with lead bullets. I did my testing with Hornady 200gr C/T bullets , which appear to be discontinued. I didn't RR the C/T bullets since I won't be able to get more , but I had previously tested 200gr Hornady XTP , producing a 2.25" 50 yd group with 3.1 BE. I think Hornady 200gr HAPs might be a viable load , and will test some when they become available again. Midway seems to be the only source for less than a 900 bullet bulk pack and they're out of stock. Since the cost per bullet is almost double that of Zero 185JHP , which shoot great, I question if I really need the additional recoil reduction. Maybe I'll hold that load in reserve for when I get even older and more sensitive. 3.3 of WST or 3.1 of BE seem to be the right loads , with BE feeling the softest, similar to 2.8 with a 200gr LSWC. The take away from all this seems to be that these barrels work well with any common bullet weight anywhere in the velocity range a bullseye shooter would use. I never tested anything above factory target loads , so I don't have any idea about defensive or bowling pin loads. Finally , the consensus was that, NO, you don't have to wear a skirt when firing these loads.

Accuracy X use KKM barrels, are the same twist in the builds and multi sight slide?

SW-52 wrote:Accuracy X use KKM barrels, are the same twist in the builds and multi sight slide?

No, AX using 16 twist barrels in 45 acp.
Jon

OK, so how do us mortals obtain one of those KKM barrels? I checked the KKM website, it doesn't seem to be listed there.

Call them.. very easy to work with

javaduke wrote:OK, so how do us mortals obtain one of those KKM barrels? I checked the KKM website, it doesn't seem to be listed there.

Their product description is "Gov't 45ACP Bushing Un-Ramped 5" , SKU is CGHSUN . This is a gunsmith fit barrel , no bushing is supplied.

Richard Benoit wrote:

javaduke wrote:OK, so how do us mortals obtain one of those KKM barrels? I checked the KKM website, it doesn't seem to be listed there.

Their product description is "Gov't 45ACP Bushing Un-Ramped 5" , SKU is CGHSUN . This is a gunsmith fit barrel , no bushing is supplied.

Right, but it doesn't specify the twist rate, so I assume it's a standard twist rate, not 1:13.

javaduke wrote:

Richard Benoit wrote:

javaduke wrote:OK, so how do us mortals obtain one of those KKM barrels? I checked the KKM website, it doesn't seem to be listed there.

Their product description is "Gov't 45ACP Bushing Un-Ramped 5" , SKU is CGHSUN . This is a gunsmith fit barrel , no bushing is supplied.

Right, but it doesn't specify the twist rate, so I assume it's a standard twist rate, not 1:13.

You're right , my invoice doesn't specify 1:13 anywhere, I assume that SKU # is for a 1:13 twist. I ordered my barrel thru support@kkmprecision.com and specified a 1:13 twist , short chambered, gunsmith fit barrel. I also had trouble finding it on the website , that's why I ordered it via email , Richard

mhayford45 wrote:Agree with Jon shooting lite slow loads in a 1:16 did eat my lunch. It was a hard and time consuming lesson to learn. 

As I have become older, I have also modified my grip to use my entire hand with what I would characterize as a medium grip pressure. Doing this is keeping me competitive and strangely feels correct as the gun/hand/fingers pressure difference feels uniform and disappears.

Can you explain why lite loads in a 1:16 are difficult to shoot? I'm trying this whole hand grip , squeezing the circumference of the grip instead of just straight back , using slightly less pressure . Still not sure what to do with my thumb. Any tips ? Richard

This is my perception and experience of working with loads at the 3.0 +- .1 grains of BE with a Zero 185 SWHP bullet, a frame mount Dot and Kart barrel for the short line only. 

The load was accurate enough for the short line and would hold near X, groups were not consistent. The load was black at 50 yards. 4.0 BE produced the most accurate groups at 50 yards.  

Function/cycling of the gun required a 10# recoil spring. less would have been better. But, I have found that mag springs and main springs become important at this level to obtain reliable functioning and had to be reduced also. So here are my observations: 

The hot cases on ejection had a tendency to come straight back into my face.    
The overall energy of the cycling of the gun was very staccato, slow, erratic and unbalanced.
This "unhinged" energy flow was challenging to control with grip pressure and trigger control suffered resulting in poorer than normal groups. 

In essence the energy of bullet and load with the weight and springing of the gun became unbalanced to the point that the system felt out of control. 

Hope that helps

Jon Eulette wrote:

SW-52 wrote:Accuracy X use KKM barrels, are the same twist in the builds and multi sight slide?

No, AX using 16 twist barrels in 45 acp.
Jon

Thanks jon. The 13 twist is recommended for jacketed or lead?

SW-52 wrote:

Jon Eulette wrote:

SW-52 wrote:Accuracy X use KKM barrels, are the same twist in the builds and multi sight slide?

No, AX using 16 twist barrels in 45 acp.
Jon

Thanks jon. The 13 twist is recommended for jacketed or lead?

Lead or jacketed , both work very well.

I have a 13 twist build on order. I need to order some bullets. Should I go with a 180 Summers flat base lswc or something else? After all these experiments is there a consensus on what the best load is for a 1 in 13 twist barrel?