My Beretta Storm goes 357SIG!

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I finally did it. Bought reamer, brass, bullets, reloading dies and reamed-out my 9mm barrel into 357 SIG. It only took 60$ for the reamer and 15 minutes in a lathe to cut new chamber in 9mm Luger barrel. Well, I have another Beretta Storm in 40 SW that will eventually (Barry do you hear me?) become 7.62x25. So, I borrowed bolt from 40 SW to make my 9mm shoot 357SIG.

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First shot and I really sorry for my old beat up Beretta, my old workhorse ain't gonna die in bed of old age. Noise level and recoil makes me think 147grain bullet is actually flying at some 1600fps or more. Shooting chrony refused to work today, it is a brand new piece and I just unwrapped it on the range and it is getting dark fast. So I guess I shall give you guys actual numbers later, once I find whats wrong with chrony.

lots of noise, accuracy went back to 2" @ 50 yards and there is some recoil at last. I think 357SIG is the end of the road for Beretta Storm, its polymer frame is getting hard pounding now. I don't think I want to hot rod 357SIG, published loads are good enough to make me worry about old girl.

For now I only tried 147grainers over 13 grains of H110, 124grainers over 14gr of H110 and 90 grainers (by far the softest load of these three) over 7.5gr or Universal. 124 grainers are still climbing at 100 yards and give about 5" groups. Well, I may be flinching and will have to verify later. 147 grainers are somewhere 3-4" at 100. I miss my 9mm Luger so much now. Factory-loaded 147 grainers (HP or TMJ's) in 9mm Luger were consistently 1.5" @ 100 and were flying at 1250 fps.
 
JohnC said:
is this a non-restricted Storm? I was thinking about the same thing- buying a .40 and getting it rebarreled to non -restricted in .357 sig
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That is the ony way to do it! If you place an order for new barrel to be made up you may as well ask for 357 SIG. Make sure your barrel is oversized all around where-ever possible because factory ones are way too light and skinny. Some smiths are just blatantly copying factory profile and make them longer but I think they are too soft for shooting heavy bullets.

Make sure your smith carries 357SIG reamer, its still fairly new chambering and reamers are not very common. My smith asked 120$ for reamer and something for work itself which I thought is a bit on a pricy side. So I browsed Brownelles and lo and behold its right there for half the price. Chabering itself turned out to be fairly straightforward procedure and I did it myself. Won;t recommend it without lathe though.
 
How exactly is this done? I keep on picturing the barrel in a vice and a hardened steel sort of bullet mold that you litterally smash into the chamber to resize it? lol, sorry but I suppose this is why I'm asking cause I have no idea.

How do you plan to go about making it 7.62X25? Is there enough recoil in the cartridge to make the rifle operate properly? Would you be looking at modifying tokarev magazines to fit?

thanks for your time
 
Brentn said:
How exactly is this done? I keep on picturing the barrel in a vice and a hardened steel sort of bullet mold that you litterally smash into the chamber to resize it? lol, sorry but I suppose this is why I'm asking cause I have no idea.

How do you plan to go about making it 7.62X25? Is there enough recoil in the cartridge to make the rifle operate properly? Would you be looking at modifying tokarev magazines to fit?

thanks for your time
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Chambering is done by reaming it out into new size with appropriate reamer. What reamer is - hmm... closest analogy would be sort of drill bit shaped and sized into cartridge.

7.62x25 - long story. I will describe it in full once project is complete. Its not as straightforward as 40SW into 357 SIG because of extraordinary cartridge lenght. Is there enough power to cycle storm? - you bet, maybe a little too much. MAgazines are way too long so Beretta's mag well goes out to clear the room and tok's mag gets two plates to mimic width or double-stack 9mm magazine. Trigger linkage is slightly reshaped too. Like I said - there will be separate report later. Once Barry wakes up and actually do what he promised back in June. Barry!! Wake the fkk up!

357SIG vs 7.62x25 would be an interesting comparison. I believe internal ballistics of 9mm-sized bore are much better allowing the use of faster powders up to the rim. Both cartridges have practically same useful case volume (about 0,87cc if I am not mistaken) but sig has bigger diameter. 147grain would be way too heavy for tokarev while its about right for sig. On the other hand tok may be loaded with as light as 70grainers and in the same weight (about 110-115 grains) BC is better for tokarev. Both are bottlenecked cartridges and both are fast in the pistol world. 357sig conversion still a better idea because of simplicity.
 
Pssssst! Dude! Somebody wrapped your beautiful black rifle in toilet paper or something!

Seriously though, that's a cool project. Good on ya for taking on something like that. And the 7.62x25mm project sounds even better. I'm curious to see how the mag-well is going to be solved. Say, do (or will you) need to convince the CFC of what you've done and have them issue a new FRT entry?
 
Pyro, I am not sure how it works, hopefully smith will change bore and cartridge the same time he verifies longer barrel and changes classification. Toilet paper - I am thinking about wrapping my laptop too! and adding pesonal touch with plastic foilage or something. Imagine posting to CGN right from the kill site?

Back to our business. I just had 147 grainers chronied at 1525 fps average of 10 shots and 90 grainers at 1945 fps, no sign of excessive pressures at all. A bit high deviation for 90 grainers -50/+35. I think I may have better luck with Power Pistol for lighter bullets.
 
Excellent on the .357SIG Storm... I'd always wanted to do that.

I'd love it if you tried some 90gr bullets once you get your Chrony working.

Awesome~
 
chronied some loads today

147gr over 13gr of H110 - 1635fps average today. Very accurate load but beat the hell out of brass so it might not be reloadable anymore.

124gr over 14gr of H110 - 1720fps.
124gr over 13.5 of H110 - 1680 fps

90 grainers over 7gr of Universal were at their 1945fps average again.
 
Excellent work, I was thinking about this as I have a 357sig barrel for my 229 and a rebarreled .40cal Storm with the heavy non-restricted .40cal barrel from Epps. You might want to talk to Beretta as the .40cal recoil spring might be a little heavier. A dual stage progressive stage recoil spring might limit the damage as well. The Storm seems to rely on the weight of the breechblock rather the spring to limit recoil. Look forward to your chrony results. also like the brass deflector.
 
Is it possible to neck down any pistol round to something like a 6.5 caliber?

Just thinking it would be nice to have an Storm that I could also hunt with in SWO
 
Snuffy said:
Is it possible to neck down any pistol round to something like a 6.5 caliber?

Just thinking it would be nice to have an Storm that I could also hunt with in SWO
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I think you can find all kinds of wildcats based on pistol calibers necked down to 22, 223, 6mm 6.5 etc. People do that. The question is if parent case has thick enough walls to handle higher pressures.

the other unpleasant thing is the fact that smaller diameter of projectile means you need even higher pressures to get same acceleration. Either that or you have to sacrifice bullet weight. Not to mention the fact that your powder-primer combinations will have to be found experimentally.
 
...or 9x25 Dillon, I think you can easily achieve 2200 fps with 115 grain bullet in 18" barrel - very hunting punch. And big hole. If synthetic frame will hold together though. At least reamers and brass are available, bullets are .355" and you will not have to cook your own recipe. I think 9mm bullets vs 6.5mm will help with internal ballistics as well.
 
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