Diving Deeper into GP100 Shooting: The Journey Starts

[SwampDweller]

In discussions with p-f members previously, the 158 gr .357 magnum HydraShoks were considered a decent choice, and they were available and were consistent in my testing for reliably firing and accuracy. I would be very open to Speer Gold Dot and Hornady Critical Duty, as both appear to be very consistent and reliable performers in virtually any caliber they're offered in. I also have a small quantity of Remington High Terminal Performance (HTP) 158 gr .357 magnums, simply because it was available from the supplier when ordering ammunition when I was running an institutional training and qualification session; in my limited testing and use, it seems decent but I am more preferential towards the above-discussed cartridges.

I think the Speer Lawman .38 Special 158 gr +P would be an excellent choice for training and practice, I've used it and found it consistently excellent-I plan on ordering some for my future practice and match use with the GP100.

Any input from those here with experience with defensive .357 magnum cartridges would be most appreciated, especially since to date DocGKR doesn't have any rated that I could find on the Ammunition sub-forum here.

Again, I really wanted the Winchester 145 gr Silvertips to work. The stuff that I obtained BNIB last year when testing didn't.

Best, Jon

Thanks. The Remington HTP 158gr is one I’ve seen some say is a decent performer, but I’m leaning towards going to the 135gr Critical Duty load as my go-to defensive load.

Regarding shooting .38 for training: how much of a problem is the ring buildup in the chambers shooting lots of .38 and then trying to load .357? How many rounds before it becomes an issue? And how can I prevent it?

I just ordered some Hogue Tamers. When the Ruger compact grips get here, I will put those on one GP100 and the Tamer on the other to see how I like each. So it looks like I’m going to Critical Duty for carry, I wonder what then would be a good training .357 load? The Magtechs work but I’m not sure they’re well suited.

What about the Barnes Tac-XPD 125gr .357?

[Flamingo]

In my gun, the 135 Hornady Critical Duty .357 shot to the same POA/POI as 158 gr Rainier Plated HP loaded in Starline 38 Special brass with 3.3 gr of titegroup.

[JonInWA]

Thanks. My first thought was to go with Hornady but after reading about how well the 140gr Silvertips performed back in the day by DB I ordered it on a whim when I saw it in stock at Lucky Gunner. I should have realized that current Winchester ammo isn’t made to the same quality standards as it used to be.

I’m probably going to go with Critical Duty as it sounds like a relatively milder load while still well within .357 Magnum territory, but what about XTPs as well? When I carry .357 it will primarily be for normal conceal carry defensive purposes.

Also, how many rounds should I put through a GP100 before I should consider it reliable enough for carry? For semi autos I’ve always gone with DocGKR’s recommendation of at least 500 and preferably 1000. Does that translate to revolvers?

Thank you everyone for the information so far. I’m on my phone at lunch so I will be able to dive in more this evening. I’m excited to really get into DA revolver shooting!

For vetting a revolver for carry, I'll do several things:

1. Field strip, clean and lubricate.

2. Dry fire to get a feel for the action and characteristics, and to see how I initially index with the revolver

3. Square-range zero with both practice/range cartridges and carry cartridges

4. Determine which holster works best with the revolver

5. Run the revolver in at least one dynamic shooting sport match-normally IDPA and/or ASI

6. Perform a qualifier/classifier with the revolver.

7. Field strip/detail disassemble as perceived needed or desirable, clean and lubricate, and apply any protective finish for duty exposures, such as Renaissance Wax for blued guns, or an exterior rub down with Sentry Solutions Tuf Cloth.

8. Load for duty, and determine best reloading devices and pouches for backup; my essential minimum is 6 rounds in the revolver, 6 rounds in a Safariland of HKS speedloader, carried in a between-the-pants-and-belt reversed Safariland CD-2 spring steel speedloader pouch, carried immediately in front of the revolver holster, and at least 1 6 round Speed Strip, normally carried in a Galco 2x2x2 pouch, upsidedown on my belt on my support side (if needed, I un-gripper the pouch flap and pull down on the Speed Strip to extract from the pouch-cartridge fit friction ensures that things don't just fall out).

9. If more reserve reload speedloaders are needed, I'll normally carry 2-3 in a Tactical Tailor case on my belt, with the location dependant on the activity/venue.

Hope that helps.

Best, Jon

This protocol (such as it is) I've found to serve pretty nicely. It ensures that the revolver properly functions, and that I also can properly function with it. Round-count wise, the process probably encompasses some 100-250 rounds.

Best, Jon

[JonInWA]

Thanks. The Remington HTP 158gr is one I’ve seen some say is a decent performer, but I’m leaning towards going to the 135gr Critical Duty load as my go-to defensive load.

Regarding shooting .38 for training: how much of a problem is the ring buildup in the chambers shooting lots of .38 and then trying to load .357? How many rounds before it becomes an issue? And how can I prevent it?

I just ordered some Hogue Tamers. When the Ruger compact grips get here, I will put those on one GP100 and the Tamer on the other to see how I like each. So it looks like I’m going to Critical Duty for carry, I wonder what then would be a good training .357 load? The Magtechs work but I’m not sure they’re well suited.

What about the Barnes Tac-XPD 125gr .357?

If you train or shoot .38 Special cartridges extensively (i.e., probably more than 50 rounds), if you need to immediately chamber .357 cartridges, brushing out the cylinder chambers will likely suffice to sufficiently remove any ring build up, particularly if you're in the field. There's really nothing you can do to prevent it, other than loading .357 cases with .38 Special loads or using light .357 magnum cartridges. In reality, the burn rings are not that difficult to deal with.

During an administrative more through after-session cleaning, use of a bronze, steel, or Tornado brush should resolve things. You can also cut a patch of lead remover cloth to patch size, and scrub out the chambers with it (but don't use it on a blued gun, as it'll remove the bluing). For cylinder chamber cleaning, I recommend using a longer chamber cleaning brush.

During an IDPA or ASI match, I carry a gunsmithing toothbrush or similar, and a chamber brush, and typically at mid-match (in a 100 or so round match), I'll go to the safety area and brush out the chambers, breech face, forcing cone, and both sides of the extracter star (and the inner portion of the back of the cylinder where the extracter star sits at rest). A clue that this is needed is if you need to thumb flush cartridges into your cylinder if they hesitate to fully chamber during reloads, or if the cylinder is difficult to close, or the trigger is difficult to pull through.

I don't have any experience whatsoever with any Barnes cartridges and little if any with the Magtechs, so I'll refrain from commenting and see what others have to say.

Best, Jon

[JonInWA]

For match/training cartridges, for .357 magnum cartridges I recommend Sellier & Bellot, American Eagle or similar factory cartridges, with bullet grain weight corresponding to carry cartridge bullet grain weight-that way, you won't need to adjust/re-adjust your sights.

I'll probably be switching to .38 Special/.38 Special +P cartridges for match and practice use; Speer Lawman, American Eagle, Remington/UMC and Norma have all served me well and without drama.

Best, Jon

[camsdaddy]

Have you been able to find any wadcutters in stock?

Precision Delta has wadcutters in stock.

[SwampDweller]

For match/training cartridges, for .357 magnum cartridges I recommend Sellier & Bellot, American Eagle or similar factory cartridges, with bullet grain weight corresponding to carry cartridge bullet grain weight-that way, you won't need to adjust/re-adjust your sights.

I'll probably be switching to .38 Special/.38 Special +P cartridges for match and practice use; Speer Lawman, American Eagle, Remington/UMC and Norma have all served me well and without drama.

Best, Jon

If that’s the case, maybe I should consider going with the Remington 158gr HTP load or Federal HydraShok 158 because all of the American Eagle .357 practice type ammo (AE and Lawman are my preferred training rounds because of QC/consistency) seems to be 158gr JSP.

[JonInWA]

That was my decision with my GP100. If the 145gr Silvertips had worked (which they didn't) POA/POI wouldn't have been significantly different from that with 158 gr bullets. I've just decided to stick with 158gr across the board to simplify my life.

Conversely, with my Security Six, I carry and practice/match using 125 gr. .38 Special +P cartridges-Remington Golden Saber 125 gr +P JHP for carry, and Remington/UMC 125 gr +P SJHP for practice/match use.

The key thing for me is sticking with the same bullet grain weight across the board.

Best, Jon

[dannyd93140]

I have fired all of these out of my GP100's just about 150,000 times.

[Edster]

If I'm carrying a .357, I'm probably worried more about animals that humans. The Remington 158 semi-jacketed/HTP is readily available and seems to do what I want from a heavy magnum-level .357. I've been very impressed with the gel tests and accuracy of the all-copper Federal/Barnes 140 grain load, too, but finding it has been more iffy. Both the Remington 158 grain and the Federal 140 grain seem to run about 1300 fps and hit about the same point of aim.

For practice, anything around 158 grain and 1300 fps hits to the sights for me.

I have a Hogue Tamer grip. It does help with recoil but I dislike the finger groove locations. Concealment is pretty hard, too. I spent a good chunk of change and time experimenting with grips over the years. They all have trade-offs between pointability, recoil control, trigger reach, and concealability. It just boils down to what is most important to the owner. I finally settled on the full-length wood panel Altamonts. Recoil control is ok, pointability and trigger reach are excellent, and they conceal as well as I could hope.