180 CMJ vs 165 CMJ

[a matt]

I know 180gr making the 165+ powerfactor have high pressures. I have to load 5.1 to get 169pf at 1.190. What about the 165gr? Less powder less pressure I assume. But the 165 will have to go faster than the 180. Is the pressure noticeably lower?

Edited January 18, 2012 by a matt

[JakeMartens]

I like 165's with 5.0/5.1 of tightgroup at 1.15

I am shooting a Brazo's full dust cover gun with 12 pound recoil spring and recoil is a quick snap and I like that better, sights track easy.

I like the CMJ's, also check out the Rainier 165 jhp

[OperationHitFactor]

I'm assuming 40, what powder are you using? Sounds like Titegroup or maybe N320 at 5.1 1.19. Which is a safe pressure, 165, 180, 200 are personal preference in regard to how the rhythm of the gun is. Most people use 180 grain and as long as you're using good brass and inspect the rounds it is generally safe. Are you having pressure signs or trying for a higher PF?

[lcs]

I know 180gr making the 165+ powerfactor have high pressures. I have to load 5.1 to get 169pf at 1.190. What about the 165gr? Less powder less pressure I assume. But the 165 will have to go faster than the 180. Is the pressure noticeably lower?

You have to use more powder for the lighter bullet.

[OperationHitFactor]

Shorting the overall length increases pressure as well. Too much crimp can cause weird things to happen as well. There is tons of info on the forums in regards to safe loads.

[twodownzero]

.40 is perfectly capable of making major within the pressure limits, even at short COALs and with all weights of bullets. The key is to not use a powder that is too fast.

We all like the faster burning powders because they are 1. more economical 2. cleaner burning and 3. produce less recoil. The only caveat is to not go too far. That's why people say not to use Clays to try to make major in .40.

Factory ammo nearly all makes major in .40. There's no need to push the pressure limit. But at longer 1.190" length, you shouldn't have any problem using most of the faster burning powders and still making major without signs of pressure.

Lighter bullets will probably result in lower pressure to make major. But you should also consider that "lower pressure" isn't really what we're after! Optimal performance (including lowest SD/ES, clean burning, and typically accuracy as well) comes at the higher pressures. If you want to figure out how to have ammo that is all over the place when you chrono it, dirty, etc., just use a powder that is too slow for what you're trying to load, and download it. Your gun will be a mess and and the performance won't be there. The reason is that higher pressure = more consistent and complete combustion.

The key is to pick a powder that allows you to load near the max book load and achieve the velocity necessary. This will give you a clean burning load with softer recoil and more consistent performance.

This has been my experience, at least. I have medium burning powders that when loaded to their potential, will make 190+ pf in .40 and probably 200+ in .45, but they will be dirty and inconsistent at 170 pf. A slightly faster powder is a better choice in that instance.

I use 180s in .40 because I prefer heavier bullets. The slide cycles slower and so the felt recoil is lower for me. Some, like Jake, who is a master, want lighter bullets at a higher velocity because they like the snappy recoil instead of the slower push. I tried 200s in .40 but they didn't feel any softer, and so I stuck with the 180s.

After you shoot a few thousand rounds of one load, you'll probably care a whole lot less about what you're shooting. But I've found that heavier bullets feel softer, at least if you shoot them the same day you've shot a similar pf load with lighter bullets. It's all preference, though, because once you get used to whatever you shooting, it really doesn't matter if you call it a "snap" or a "push," recoil is just recoil, and the sights determine when you pull the trigger again.

[a matt]

Solo 1k. And crimp is .442. Thanks for the 411. That help alot.

[a matt]

Edited January 19, 2012 by a matt

[OperationHitFactor]

I personally never found a load of Solo 1000 I liked in 40. Lots of guys swear by it though. It always seemed a bit harsh to me, but I always had good results with Titegroup and N320. On the other hand, I like solo 1000 for 45 a lot. I've never found the perfect powder that works for every caliber for me.

[blaster113]

for a 5" gun I would use the 180 CMJ, for a light 6" gun I would stick with the 165's. My new 6" feels better with 165 grain loads compared to my old 5" loads