Anyone loading for Glock 17L or converted 24?

[Bullseye25]

I have a Glock 24, which is the .40 version of the Glock 17L. 6" barrel.

I have a 9mm conversion barrel that works great for it. But I'm having trouble with my 124 gr LRN loads with HP-38/Win 231. OAL of 1.131 ( a bit long, gonna try shortening to 1.125 to increase pressure a bit, data recommends 1.125)

I'm using 4.3 grains, which is 0.1 grains short of max load for the data I've found. I've noticed it still barely has enough energy to cycle the slide for proper ejection. I get extremely weak ejection and an occasional stove pipe. It already has a reduced recoil spring down to 11lbs.

With 4.2 gr of Unique I get better ejection and much less stove pipes. I heard with lighter bullets and lighter loads, faster burning powders should get better slide operation than slower powders. I'm experiencing the reverse effect.

Is anyone else loading for the 17L or converted 24?

 

[MrCountyCop]

Ok so I cant read this early in the morning *Delete Me Please*

 

[LiveLife]

Hodgdon list 4.4g-4.8g in W231 for the 125g bullet so you may be a little light on your loads.

Actually no. 4.4 - 4.8 gr is for jacketed bullet (FMJ) and OP is using 124 gr Lead RN.

The current published load data is for lead Cone Nose (CN) which has different nose length, bearing surface length and bullet base seating depth than RN bullets.

125 gr Lead CN W231/HP-38 .356" OAL 1.125" Start 3.9 gr (1009 fps) 25,700 CUP - Max 4.4 gr (1086 fps) 31,200 CUP
125 gr Sierra FMJ Winchester 231 .355" OAL 1.090" Start 4.4 gr (1009 fps) 24,600 CUP - Max 4.8 gr (1088 fps) 28,800 CUP

I'm using 4.3 grains, which is 0.1 grains short of max load for the data I've found. I've noticed it still barely has enough energy to cycle the slide for proper ejection. I get extremely weak ejection and an occasional stove pipe. It already has a reduced recoil spring down to 11lbs.

If you are using older 125 gr LRN profile with more pointed nose and stepped shoulder, you may want to consider using the shorter/more rounder LRN that provides longer bearing surface which will get seated deeper in the case neck and produce more consistent chamber pressures, greater accuracy and less leading. I used to use stepped RN bullet but found CN with longer bearing surface to be better and now prefer the shorter/rounder RN with just as long of bearing surface as CN (see comparison picture above). I am using G22/G23/G27 with 40-9 Lone Wolf/KKM conversion barrels with the shorter/rounder RN bullet and my loads will reliably cycle the slides with the stock recoil spring assemblies which is 17 lbs.

With the Missouri 125 gr RN (SmallBall), I use 1.080" - 1.110" OAL and 3.8 - 4.0 gr of W231/HP-38 based on 1999 Winchester load data (Dardas also offers the 124 gr RN with shorter/rounder nose).

If you load the shorter/rounder RN bullets to more typical 1.125" OAL, the bearing surface may hit the start of rifling, depending on the barrel you use (see white arrows).

 

[Bullseye25]

That is data for FMJ. I'm using lead. My listed range is 3.9 - 4.4. Most of the data I found is exactly that for 231.

 

[LiveLife]

For faster and more consistent chamber pressure build up, you want to use the longest OAL that will work with your pistol/barrel/magazine.

The key is when the "bearing surface" of the bullet base will start to engage the rifling. The shorter/rounder RN will have shorter working OAL of 1.080"-1.100" than the typical pointed/stepped RN at 1.125" but the bearing surface above the case mouth will be the same.

Since the shorter/rounder RN will have more bullet base seated inside the case neck, chamber pressure will build faster and more consistently to reliably cycle the slide, even with 17 pound factory recoil spring rate and produce greater accuracy, which I assume you are looking for using G24.

Check out my posts #39, #42 and #45 on this thread - http://www.thehighroad.org/showthread.php?p=8472049#post8472049

 

[LiveLife]

Another thought. If you are getting slide cycling issues with over max lead load data using lighter than factory 11pound recoil spring, your bullet maybe too hard and the bullet base not deforming to allow more gas leakage (obturation).

If you are using 22-24 BHN bullet, consider using softer 16-18 BHN bullets.

Are you having any lead smearing issues near the chamber?

 

[918v]

I have both s G17L and a G24. The reason your G24 is choking is because the G24 slide weighs four ounces more than a G17L and they both share a 17lb recoil spring.

You need a full power load at the least. The G17L slide has so much metal removed from the innards it weighs the same as a regular G17. There are lightening cuts to the rear of the breechface, on both sides of the barrel channel, and the window on top is bigger. The muzzle area has also been relieved more.

My G17L runs with 3.5grs of 231 under a 125gr lead TC bullet at 1.040" OAL. It also runs with 3.2grs of Bullseye.

 

[LiveLife]

918v, OP is running 11 pound recoil spring on the G24 with 40-9 conversion barrel.

Since the 4.0 gr W231/HP-38 with 125 gr LRN load works reliably to cycle the slide on my G22 with 17 pound factory recoil spring, I am guessing that OP's G24 with 11 pound recoil spring should cycle the slide with 4.3 gr load.

I am thinking that his loads are not generating sufficient chamber pressures due to various reasons. I don't think not enough powder charge is one of them.

 

[Bullseye25]

I'm not sure what the hardness of the bullet is. I can probably call the manufacturer. They are Space Coast Bullets out of Melbourne, Florida. I called them and they said they are an 8 of 10 on the Seiko scale. They stated they don't use BHN anymore and she didn't know what the equivalent rating would be. Without any knowledge of this scale, being 8 out of 10 sounds like it may be on the harder end. They are shaped like the Dardas RN in the picture above, they have the shoulder on the base like a swc.

If the case is that they are a bit on the too hard side, what should I do? Push them harder? Is anyone familiar with the Seiko scale for hardness?

***I actually called in the middle of writing this, hence why It didn't make sense in the beginning*** (Edit)

 

[Bullseye25]

BDS,

So what you're saying is if I set it deeper, from the 1.131 OAL to the 1.125 OAL, I can get a bit more chamber pressure? I know deeper bullets create more pressure. I guess what I'm asking is will the difference I just stated be enough to noticeably increase slide cycling?

 

[LiveLife]

Seating the bullet deeper for your "stepped" LRN bullet may not resolve your issue as now the bearing surface of the bullet base has to travel longer and a lot more high pressure powder ignition gas will leak around the bullet, which will decrease the chamber pressure further and may negate any gain from seating the bullet base slightly deeper.

My guess is that the bullet you are using is too hard with not enough bearing surface to allow sufficient chamber pressure build up to reliably cycle the G24 slide, even with lighter 11 pound recoil spring and with the higher 4.3 gr charge of W231/HP-38. Softer bullet with longer bearing surface will obturate better to seal the high pressure gas and may work better for you.

If you like, PM me your address and I'll send you an assortment of 9mm bullets I have on hand so you can see which bullet works best for your G24 and barrel.

 

[LiveLife]

Space Coast Bullets ... they said they are 8 of 10 on the Seiko scale. They stated they don't use BHN anymore and she didn't know what the equivalent rating would be.

I think they meant Saeco hardness tester that uses 0 - 10 scale - http://www.redding-reloading.com/in...view=article&id=84:saeco-lead-hardness-tester

According to the comparative chart on the link, 8-9 on saeco scale correspond to 16-17 on BHN and 10 is 22 BHN.

So if the bullet is 16-17 BHN, 4.0 gr of W231/HP-38 should be more than sufficient to deform the bullet base, and certainly at 4.3 gr.

Are they sized to .356" and have you slugged the aftermarket conversion barrel for G24 to see if the groove diameter is .355"/.356"?

 

[918v]

Seating that bullet a little deeper sill not raise pressures significantly. 3.8 grs of 231 at 1.040" OAL only makes 1050 FPS in a 6" barrel. You are prolly way under that with your longer OAL even with s higher powder charge. I suggest you up the charge to max. That slide is real heavy, it weighs the same as a G20 10mm slide.

 

[Bullseye25]

I have not slugged the barrel. The bullets I'm using are .356 It works well with Unique so I'm just trying to figure out why I'm getting these results with 231.

So what if I extend the OAL a bit. Will that work since it will sit closer to the rifling and get less leakage as pressure builds???

I'd like to find a good accurate load with the 231 because I can get more rounds for less powder and many have found accurate loads with this powder for their pistols.

 

[918v]

Extending the OAL will not solve your issue. It will lower the pressure further.

 

[LiveLife]

Bullseye25, I am curious. Does factory target loads like Winchester white box ammo reliably cycle the slide on your G24?

 

[Bullseye25]

Haven't tried yet but sounds like it might help me figure this out.

 

[Bullseye25]

I tried out some factory Remington Green box 115gr. They cycled a little better than my loads. I'm starting to think it is just the slide being extremely heavy. What I forgot to try was shooting the factory loads with the 17lb stock spring. I don't think it would function well like that either. I didn't get any stove pipes yesterday with 4.25 grains of 231 at 1.125 OAL.

 

[918v]

You'll prolly need some 124gr+P to run that gun with the stock spring.