[chazgin]

I bought a .400 Corbon barrel andsome RCBS dies and started loading. I have noted problems with flowing and severely flattened primers. Some primers would show very high pressure signs, and others would look just fine. This problem happened with both handloads and factory ammo.

It seems there is a problem with this round in that there is not enough neck to hold the bullet in place. Chambering a round slams the bullet against the feed ramp. This will almost always set the bullet back in the case to some extent. I then bought a cannelure tool to roll cannelures into the non cannelured 135's. I roll crimped the bullets so hard into the case that the neck bulged and would not feed into the chamber (backed off then so it would fit). It seems you can't crimp the case neck hard enough to prevent this from happening. What was happening is that the bullet was sometimes pushed too far back into the case, decreasing the case capacity. I think this is leading to an overpressure situation.

Try this experiment: measure the OAL of a live cartridge (factory or handload). Chamber it in your gun and pull it back out. Now measure the OAL again. It will probably be shorter. Not good.

At this point I'll try lead bullets. AA has some lead bullet loading data in their latest manual.

Is this another of Peter Pi's ideas that hasn't panned out?

 

[Charlie Petty]

I think you're exactly right about not enough neck. And those flat primers are good evidence of what happens to pressure when bullets get pushed into the case.

I did some loading with it early on but didn't get much interest so didn't go too far with it.

You might be able to adjust the magazine lips to let the round go a bit sooner so the bullet doesn't smack straight into the ramp. The ideal would be for the case shoulder to hit the ramp first.

 

[chazgin]

did some loading ?

What were your experiences? I've talked to some other guys and they had trouble also. I never thought of it but next time I'm at the range I'll single load rounds and see what happens.

 

[csmkersh]

Re: did some loading ?

did some loading ?

What were your experiences?

:rotflmao:

 

[Charlie Petty]

Same as yours. The data that CorBon published seemed to be accurate in terms of velocity so I didn't try other powders. I have RCBS dies with a taper crimp that worked pretty well.

 

[csmkersh]

My experiences with my Savage 116FLSS in .308 Win has been less than sterling. :banghead: I'd been trying various light loads of IMR 4895 and Varget and getting nowhere. I was about to decide the gun wouldn't shoot.

In desperation, I bought a box of Remington 165 grain Ballistic-Tips and give it a try. :idea: The SOB (that's Sweet Ol' Boy for any ladies or youngsters who might be watching) shot me a 3/4 inch group!!! :hypercolor:

So, looks like that with this particular rifle I need to keep MV around 2700 FPS.

At least you two seem to be doing okay with the S&W 500. :bow:

 

[Charlie Petty]

Gee Sam... how fast were your "light" loads going? What sort of bullet?

If it says "Ballistic Tip" the odds are that it will shoot more accurately than your average brickbat...

Ask me about the 500 tomorrow night. Gonna shoot it some more in the morning

 

[csmkersh]

Gee Sam... how fast were your "light" loads going? What sort of bullet?

If it says "Ballistic Tip" the odds are that it will shoot more accurately than your average brickbat...

Well, if the Hornady book is anywhere near right, about 2250 FPS with the Varget and about 2400 with the IMR 4895. As to bullets, Sierra Gameking 2145 (165 gr), Matchking 2200 (168 gr). Nosler Partition 16330 (165 gr) and Speer Grand Slam (165 gr). Primers were CCIs and brass was often reloaded Lake City. I've got new, unfired Remington brass I'll use next time around... And I really need to buy a good, Texas made chrony --- say Oehlers and stop the guess work.

Oh, and I bought another box of the Remington Ballistic-Tips. They've supposedly refined the load and renamed it the Accu-Tip and in a Gold box rather than the green the Rem Priemer stuff comes in.

 

[Charlie Petty]

That may be just a little too slow. IMX the .308 shoots better near the top of the scale.

Don't forget that both the best chronographs are made in Texas. Oheler in Austin and PACT in Grand Prairie. Actually the real "Chrony" is an exceptionally good buy and works just fine.

 

[csmkersh]

Actually the real "Chrony" is an exceptionally good buy and works just fine.

I didn't know Pact was a Texas product. I like both their & Oehler's warranties. I hadn't thought a whole lot about the Chrony but welcome any feedback as to which model you might recommend.

 

[Charlie Petty]

It really depends on what you want to do. I use both Pact and Chrony chronographs with printers because I want to document everything and it's quicker that writing all that down.

You can buy a very basic Chrony for around $75-80 and the basic PACT is around $120. I think it does some statistics as well.

I haven't seen an Oehler price in some time.

I've done comparisons with all sorts of different chronos and they all measure velocity more accurately than we need. The Chrony has a one foot screen spacing and reads just the same as one with a 4' space.

 

[csmkersh]

It really depends on what you want to do. I use both Pact and Chrony chronographs with printers because I want to document everything and it's quicker that writing all that down.

I'd like a printer or memory and PC link - better yet, both.

You can buy a very basic Chrony for around $75-80 and the basic PACT is around $120. I think it does some statistics as well.

That's one of the things I like about the Oehler - that and its third screen to watch for errors.

I've done comparisons with all sorts of different chronos and they all measure velocity more accurately than we need. The Chrony has a one foot screen spacing and reads just the same as one with a 4' space.

Great! Natchez Shooter's Supply sometimes runs specials on the Chrony. I'll have to keep an eye on their web site.

 

[Fernando Coelho]

You can also get a Chrony here. There is also a printer available for the Chrony.

 

[csmkersh]

I don't always have to go to the ranch to step in it...

Thanks, Fernando. I'll take a look see...

 

[Fernando Coelho]

Don't worry about it

The F-1 Alpha is probably the best bet, price & feature wise, of the different models. You can also plug the printer into it. As a Gold Club member you would get the lower listed price.

Fernando

 

[Charlie Petty]

I don't know about the PC link. I know the PACT has an ir data port that you can dump to the pc, but I don't know how many shots it holds.

If you really want to get serious the Oehler Model 43 hooks directly to a laptop and can do all sorts of cool stuff inclunding pressure measurements and acoustic group measurements that are within the nearest microtad... but it costs a heap.

FWIW: I haven't seen a case where the extra screen really proved anything. Normally if the chrono messes up it is so obvious it jumps up and bites you. That extra screen also makes it need a 4' spacing which is sometimes inconvenient.

Why don't you check the various web sites?

 

[LIProgun]

I resisted buying the Chrony printer for several years, and finally broke down when Natchez had it on sale. I soon realized how much time I wasted hand writing data sheets. The printer is a real pleasure!