Critique my crimp!

Looks good to me. Maybe a little heavy for .38, it would be a perfect crimp for a .357magnum with 2400 or H110.

I use Trail Boss in 45 Colt, I crimp but no where near that heavy, and I don't have issues. I'd say you could back it off a bit.

Looking good. That crimp will work with the TrailBoss.

The only thing is it will wear out the brass pretty quick, belling and crimping work hardens the mouth area and causes neck splits.

Try backing off on the next batch, you want just enough crimp so when you run your thumb nail over the case boolit junction it won't catch on the case.

Same with expanding the case mouth , just enough to keep from shaving lead off the boolit.

It's really hard to tell by the photo's not saying they're poor quality, it's just hard for me to tell by looking at a pic.

It's really a type of hands on thing for me.

Some times you can tell when looking at a fired case, if it still has some crimp at the mouth you need to back off a little more.

You'll get the hang of it just takes some time at the press and at the range !

I'd say they're both a little on the heavy side for .38spl. They'll work, but I'd go with a little less crimp unless testing your loads confirms that the Trail Boss requires that much. On a light/medium/heavy scale, that first one looks heavy for sure, the second one looks closer to medium but still heavy. And looking at that first one, you might consider backing off your seating stem 1/2 a hair. But again, they both look useable.

Way too heavy! That is a very light load, probably just hitting 700fps.

Fact is, with a load that light you likely need no crimp at all! The primary purpose of the crimp is to prevent "bullet jump" under recoil, and that load won't be producing much. I don't think you need a heavier crimp for consistent ignition. TrailBoss was designed for light cowboy loads and is rather bulky. Test to find out. Measure OAL of your rounds. Load two rounds, one opposite the other. Fire one. Measure the other to see if the bullet has "jumped" out of the case at all. Do it a few times on the same round. If you are getting jump, then you need some crimp, but only a very light crimp with a load this light.

If you feel you must crimp anyway, do so as lightly as possible. Your cases will last a lot longer that way.

Remember that case neck tension is the first line of defense in holding a bullet in place. After seating your bullet do the "press test" to make sure the case has enough tension.

You absolutely need no crimp (other than to just remove the "flare" from the expander die) in the Mod. 52. Do ensure sufficient tension with the press test. It's case neck tension that prevents bullet setback in autos, not crimp.

As to the carbine, you "might" need a crimp. Test by measuring basic OAL then OAL of rounds in mag after a few rounds have been fired. Also measure a few rounds after having been chambered. React accordingly.

It takes some kahonies to put a pic up in front of this crew for critiquing. Good for you.

Potatohead said:

It takes some kahonies to put a pic up in front of this crew for critiquing. Good for you.

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I'll be doing the same thing when I get ready to work on a deer load for my dad .357 magnum so I can try and harvest one this year with a revolver. Lol

That's the kind of crimp I'd use on my .458 Win Mag Back off a bit.

It looks like you are crimping to a grove in the picture (also find crimping into a soft lead bullet but not a hard case one). I used to load .357 SIG for a friend and he kept insisting on a crimp until I explained that his bullets don't have cannelure in the right place for the SIG and merely crushing the case would actually weaken the neck tension and make the bullet looser.

Mike

I too believe your original photo depicts a very heavy crimp. I don't crimp my 44 mag loads quite that much. Over the years with revolver rounds I crimp much less than when I first started reloading. But then in the early days I always thought bullet tension was primarily due to the crimp. Now I realize that neck tension is actually more important.

I would put a very slight roll crimp on that load.

Arizona_Mike said:

That's the kind of crimp I'd use on my .458 Win Mag Back off a bit.

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Same here with my .460 S&W mag.

Truthfully tho, other than premature case mouth failure from overworking the brass, a crimp that is too heavy will not harm a thing unless you are buckling the case or deforming the bullet while doing it. Many slow burning powders demand heavy crimps to ignite completely....TrailBoss does not fit into that category. As you get more experience your confidence with crimping will increase and you will find yourself crimping as minimally as possible to prolong brass life. Rule of thumb is the heavier the recoil, the heavier the crimp. Light recoiling loads only need neck tension to hold them in and only enough crimp to remove the flare used to seat the bullet. Ammo to be used in tube feed carbines, I crimp moderate to heavy regardless of load.

I don't recall ever hearing Trail Boss needs a heavy crimp. Like said above, usually slow powders need a heavier crimp and Trail Boss is not a slow hard to ignite powder.

IMO that crimp would be excessive for a .357 Magnum let alone a .38 Special. I would back off a lot... You do need some crimp in a revolver cartridge especially when it will be used in a tube fed Carbine.

My first batch of .357 had too little crimp and failed the push test on half a dozen bullets. i put a quarter turn on from there and could just barely visually detect the crimp, but it held just fine out of my GP100 for 50 rounds. also passed the push test just fine.

i'm a noob, but my experience is that a little crimp goes a long way.

My first batch of .357 had too little crimp and failed the push test on half a dozen bullets.

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If you seat bullets and they will not pass the push test without a crimp?

Your expander is over-size, you have out of spec thin brass, or an over-size sizing die.

One of the three.

You simply should not be able to push a bullet deeper in the case with your fingers with no crimp!i
If the case neck tension is as it should be in the first place.


A .357 expander should measure NO more then .355", tops.

rc

I'm with RC, there's no substitute for good neck tension on any caliber, particularly on uncannelured rifle bullets and semi auto pistols where you don't want setback issues. A heavy crimp will also shorten your brass life. I typically only crimp moderately heavy on full house magnum calibers, exceptions being something like heavy bullets in J frame snubbies and the like.

I agree with RC, I do not see enough case bulge from the bullet. What diameter are those SWC's ?