OAL .38 Super with SR4756 and compressed load

[964]

As mentioned in an earlier post, I am new to loading the .38 Super. I'm finding that loads from 8.2 grs of SR4756 are compressed with the MG 124 jhp. Looking thru the threads, it looks like folks are using from 8.4 up to 9.0 at an oal length ranging from 1.235 to 1.255 and even .260!

So the question is whether my scales are off (balance beam) or you guys are compressing the heck out of the charge.

I'm loading for a BarSto w/ one bbl port and an EGW 6 port comp.

Thanks,

Lynn

[XRe]

4756 results in a compressed charge, no doubt. However - it does seem that the powder charge comes out of the measure somewhat "fluffy". If you tap the case a little bit, it will settle slightly (or, at least it seems to). So, there's a lot of air there that gets compressed, too... But, most slower powder race gun loads end up compressed. Nothing wrong with it. You should see my N105 load!

Load to 1.235" to maybe 1.245" for best feeding across the board...

I'm relatively close to you, geographically - if you need it, PM me for my phone number. Be happy to chat w/ you about it on the phone

[964]

Thats good news! I was pretty sure I read somewhere they were compressed loads, but couldn't find the post to verify. Sounds like everything is normal but I will have to squeeze the case a little more during bullet seat, to hold the length until it gets to the Lee Fctory Crimp Die.

Thanks for the reply and I'll PM you.

Lynn

4756 results in a compressed charge, no doubt. However - it does seem that the powder charge comes out of the measure somewhat "fluffy". If you tap the case a little bit, it will settle slightly (or, at least it seems to). So, there's a lot of air there that gets compressed, too... But, most slower powder race gun loads end up compressed. Nothing wrong with it. You should see my N105 load!

Load to 1.235" to maybe 1.245" for best feeding across the board...

I'm relatively close to you, geographically - if you need it, PM me for my phone number. Be happy to chat w/ you about it on the phone

[boz1911]

Have you chrono'd yet? My gun will easily make major with 8.2 and 124 MG's..

[964]

I have not. I just started the process this afternoon and was putting together some test rounds. Will chrono and check primers when I get to the range. I have a couple of things I want to check that may be causing the inconsistent oal, besides powder compression.

thx,

lg

Have you chrono'd yet? My gun will easily make major with 8.2 and 124 MG's..

[itento]

My buddy and I have worked up a great load with 7625. We're running 7.5 gr to 2.242 OAL with MG 124 CMJ and running in Brazos and Dawson guns with poppets. Cronoed at Area 6 in cool/cold weather at 169.7. Very consistent. We both really like this load.

[G-ManBart]

Ditch the Lee FCD!

Seriously, if you're using a decent resize die and aren't using totally worn brass, they're not necessary. In fact, they can actually cause problems because of how they work the case. It squeezes the whole case, which means it's squeezing below the bullet....which can cause you to lose neck tension, which is bad. The other thing is that they work the case when it's going in and when it's coming out, which I'd suspect leads to earlier brass fatigue since it's working it twice as much. For some applications they might be helpful, but they're really not needed for Super/Supercomp with jackted bullets and decent brass. R,

Thats good news! I was pretty sure I read somewhere they were compressed loads, but couldn't find the post to verify. Sounds like everything is normal but I will have to squeeze the case a little more during bullet seat, to hold the length until it gets to the Lee Fctory Crimp Die.

Thanks for the reply and I'll PM you.

Lynn

[XD Niner]

IMR 7625 is not recommended by Bob Londrigan for his guns. You can contact him for the reasons.

Edited November 29, 2008 by XD Niner

[norbs007]

And I'm sure he meant 1.242 OAL

[964]

I had to put the project on hold today for a 2nd Thanksgiving. So, if the OU/OS game is boring, I'll get back on the seating/sizing mystery.

Thanks for all the advice, guys.

lg

[bwit]

964, I don't know if you are aware of this but for your own safety, standard procedure for each loading session should be to zero your balance beam [recheck it and adjust it to read zero with an empty pan] or if it is moved or bumped. Then and only then do you KNOW it reads correctly. Moving the scale, temperature changes, its level and lots of other things will change it's readings. You could also, after you zero it, make a small copper or aluminum wire check weight. You can make it any weight you wish but ideally it should be in the neighborhood of the load weights you are using. Example: 6.0 gr of powder, a 10 gr check weight is ok. Then rather than zeroing the scale you can weigh your check weight to verify the scale reading, since you know what it really weighs after the scale was zeroed. Of course, if the check weight does not read properly you'll have to zero the scale anyway. Another advantage is that if the scale at some point gets damaged or dropped or ??? by you or unbeknown to you, you have any easy way to determine if it is working properly with your check weight. I'd write the check weights value on it with marker or engrave it, both of which are easier if you can flatten part of it with a hammer, just enough to write on. I bend it into a small circle with a handle so it stays within the confines of the scale pan. Lots of luck and happy reloading.

Edited November 30, 2008 by bwit

[XRe]

No fear - Lynn knows what he's doing. He's just new to loading for an Open gun, and didn't realize that it was normal to run compressed loads with the slower range of powders. So, he wanted a gut check that he wasn't really mistaken on using his scale I think he's good to go, after speaking w/ him privately...

[964]

Hi Guys,

I appreciate bwit's concern. Yes, I have checked the zero on the beam scale and do so as he correctly suggested any time it is moved, disturbed etc and I keep it dust free. Like XRe said, I did not have experience with .38 Super at IPSC PF and I was not sure about the compressed charge, so I asked, before pulling a trigger.

Everything is in order and the test loads are ready to go. I appreciate all the responses to my questions and to XRe for the time he sent on the phone discussing .38 Super loading.

I look forward to getting a load worked up, spending some time on the range with the new blaster and then coming to a match and meeting you guys.

lg

No fear - Lynn knows what he's doing. He's just new to loading for an Open gun, and didn't realize that it was normal to run compressed loads with the slower range of powders. So, he wanted a gut check that he wasn't really mistaken on using his scale I think he's good to go, after speaking w/ him privately...