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Old 01-19-2013, 10:04   #4
SDGlock23
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I've found Longshot to have a certain characteristic about it. I've had some for a while now and what always bummed me out about Longshot was that it just seemed like I could never get out of it what Hodgdon claimed. I would load up to book max and even in a longer barrel would come up noticeably short in velocity. Not only that, but often the velocity would be erratic with wide spreads. Driving it faster seems to make it more consistent.

Keep in mind I run these loads through my Gen4 G35 with a 6" G24 KKM barrel installed. It has better case support than the stock barrel and the added length is a plus. I used to load for the 10mm but recently got rid of it, and I've been keeping my eye on what 10mm guys are doing in their setups for quite some time.

One thing you'll notice right off the bat is that most who load for the 10mm end up buying aftermarket barrels for their 10mm (often 6") and then they start in with their "warm" handloads. Go on over to the 10mm reloading section and see for yourself, there are loads listed there that are anywhere from 10% to 25% over book max charges.

As with all things, this is a topic of debate, but I feel (as do others) that the .40 S&W case is stronger than the 10mm case. Notice how all three cartridges, one based off the 10mm, one based off the .40, have a different max PSI rating. 10mm is rated at 37,500 PSI, the .40 S&W is rated at 35,000 PSI and the 357 Sig is rated at 40,000 PSI. But why?

Here is my question, why isn't the .40 also rated the same as the 357 Sig? Why isn't the .40 rated, at the very least, the same as the 10mm? I know that the .40 case isn't any weaker than the 10mm or 357 Sig case.

The .40 and 357 Sig use small primer pockets while the 10mm uses a large primer pocket. To keep it short and sweet, there's more material in the case of the .40 and 357 Sig than there is the 10mm, and more material means more support. Additionally, the .40 was originally rated for 35K PSI and several years later it was beefed up, but the 35K rating never changed, and hasn't so far. IMHO, there's no reason the .40 shouldn't be rated for 40K PSI as well.

What I'm getting at is this, 10mm guys are loading well beyond book max in a case that's not quite as strong as the .40. What I've been messing around with for quite some time is doing the same thing as the 10mm guys do with their 10's, but instead I'm using a .40. I've gotten some very interesting results, but I've already come to the conclusion that there aren't too many loading the .40 to what it's capable of.

Back to Longshot, I've figured out that in the .40 you need to go slightly over book with LS to make it come alive. Please note, my results are from my setup and I DO NOT advise anybody to use my data in their gun, it's not plug and play. You can use my data for reference, but if you decide to get the most out of your .40, first off work up your loads and secondly make sure you have an aftermarket barrel with better case support. A heavier recoil spring is recommended as well (22-24lb) and a comp would help out too.

I haven't messed around a lot with 135gr or 200gr in Longshot, but I have some interesting figures for the rest. I use CCI SP primers and 1x Federal ("Federal" stamped, do not use "FC" stamped) brass. Velocities are averages from the 6" G24 KKM bbl. NOTE: I feel 10% over book is about it, don't go beyond. As you see, there's no reason to push it further.

180gr Montana Gold JHP, 8.5gr Longshot @ 1.130" = 1,327 fps (approx 6% over book max)

180gr Montana Gold JHP, 8.8gr Longshot @ 1.125" = 1,402 fps (10% over book) That's 786 ft-lbs!

165gr Gold Dot, 9.0gr* Longshot @ 1.130" = 1,412 fps (See * below)

165gr Gold Dot, 9.5gr* Longshot @ 1.130" = 1,485 fps / 808 ft-lbs!

155gr Rem JHP, 10.8gr Longshot @ 1.125" = 1,554 fps (8% over book max) That's 831 ft-lbs!

*Hodgdon data is low for the 165gr, but I know why. They use the 165gr Sierra JHP, which is a rather long 165gr JHP. The 165gr Gold Dot is considerably shorter. Based on what Hodgdon claims for the other bullet weights, I calculated that a 165gr Longshot charge should be around 9.0-9.2gr.

As I mentioned earlier, a lot of the "book" Longshot loads weren't very consistent, but driven a little harder the numbers got a whole better and the velocity spread tightened down a whole lot too. Longshot is a fairly slow burning powder and it meters very well also, which is a plus, and it's somewhat common too. Maybe this will inform some people of what the .40 is capable of.
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Last edited by SDGlock23; 01-19-2013 at 10:13..
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