Revolver Bullet Seating

Bucksnort1

New member
In my topic on reloading for Rossi lever gun in .357, someone said to seat revolver bullets to the cannelure.

I loaded some 38 spl and .357 mag test rounds with Frontier 158 grain bullets. These bullets have a cannelure. I seated the 38 spl bullets for a C.O.A.L. of 1.550" and the .357 mag bullets for a C.O.A.L. of 1.590". The mag bullets seated to the cannelure but the 38 special bullets seated to just below the cannelure. I test fired all of them from a mag handgun. The 38 spl recipe called for fewer grains of Unique (same powder for .357) but they seemed a bit weak. Is this because of the increased case volume by not seating to the cannelure?

Should I always seat to the cannelure if the bullet has one? Berry's .357 bullets do not have cannelures.
 
How much unique? A starting load of unique will be soft, inconsistent shooting and dirty burning. I typically use 5 grains in 38 special for 158 grain lead bullets and it makes a nice full power load that shoots clean. Loading JUST below the cannelure will lower pressure because you have more room in the case but I don't think it would make them feel "Weak" unless you were unable to crimp well and you had poor bullet pull. I would seat to cannelure unless you have some compelling reason not to. If you have a legitimate need to seat outside the cannelure I find a taper crimp die is handy.


Hope this helps,
Mike
 
.38 Special will always feel weak compared to .357. Without knowing all the details of your load all we can do is guess. A lot of the starting loads listed for 38 Special are very weak and noticeably softer than the vast majority of commercial loads.

The difference between 38 Spl and .357 brass should be around .13". Using the same bullets the OAL should be different by about .13. Seating bullets out further will reduce the pressure. Seating bullets deeper will raise the pressure. How much of a difference will depend on which powder you are using and how much of that powder you are using.

You could try seating bullets into the cannelure and seating the bullets longer to see if you can even notice the difference.

Plated bullets do not have a cannelure, but anyone experience in reloading should be able to determine an appropriate OAL.
 
"...always seat to the cannelure if the bullet has one..." Nope. You're not seating to a depth. You're seating for an OAL.
You can forget the cannelure altogether for .38 Specials. Either way, the cannelure is irrelevant. Your OAL's are SAAMI max OAL's. Leave those alone. They work.
As mentioned, .38 loads will always have less felt recoil.
5 grains of Unique in .38 Special is very slightly over max for a 158 grain cast bullet.
 
These bullets have a cannelure. I seated the 38 spl bullets for a C.O.A.L. of 1.550" and the .357 mag bullets for a C.O.A.L. of 1.590".

There's a lot of opinions here, obviously. I first loaded 38 Special on 6/4/1984; and have been doing so ever since. Easily many 10's of thousands; probably touching the 100-grand neighborhood. So I have a bit of experience on this one. It's my most loaded cartridge - by far. Here's my opinion:

If a revolver bullet has a cannelure (or crimp groove in the lead world), then that is the designed seating point for that bullet; and is likely the best place to seat the bullet. The calipers can stay in their case. Every 38/357 bullet with a cannelure or crimp groove that I load, gets seated to that groove. Loading them as designed. This approach has served me well for over three decades. I have tried other seat points. But save the full HBWC, I never gained anything by seating at some depth other than the cannelure/crimp groove.

A starting load of unique will be soft, inconsistent shooting and dirty burning.

Unique is a bit of a tricky propellant. In 38 Special, with a 158 grain bullet, it works fairly well. But to get it running well in 38 Special, you gotta go up to the top of the pressure scale for the cartridge. Since you are shooting them in a 357 Magnum firearm, going a little over SAAMI spec pressure for the 38 Special cartridge isn't a major concern. I'm not suggesting to routinely load 38 Special over spec, I'm just saying that you have a lot of safety "headroom" since the firearm being used is designed for the much higher pressure Magnum cartridge.

I load Unique in 38 Special with 125 grain bullets (both X-treme's plated FP's, and JHP's); and I load 'em up 'till they run clean; and that's near the top of the load data charts. Do your own work ups, of course.

I've loaded lots 158's with Unique too; but I don't really care for the combination these days. It's a good enough combo; just doesn't fit my shooting style.

So there's one guy's opinion. And was worth every penny you paid for it :p
 
You can forget the cannelure altogether for .38 Specials. Either way, the cannelure is irrelevant.

That is not correct for loading a cartridge that will ultimately end up in the lever gun with a tube magazine.

Crimp them to the canular so the spring in the tube magazine doesn't shorten your OAL by pushing the bullets into the case further than they were when you seated them.

That will raise pressure and can raise it to a dangerous level for either the 38spl or .357 magnum cases.
The .357 magnum cases will have less recoil with the same amount of powder that the .38 SPL have with the same bullet.
As said above it's due to the extra length. if your planning on shooting these out of a lever action then crimp to the cannular no matter what, that's why it is there.


5 grains of Unique in .38 Special is very slightly over max for a 158 grain cast bullet.

You already mentioned this. If the bullet slips due to not being crimped and collapses into the case further, raising pressures higher, What do you think will happen.
 
"...always seat to the cannelure if the bullet has one..." Nope. You're not seating to a depth. You're seating for an OAL.
You can forget the cannelure altogether for .38 Specials. Either way, the cannelure is irrelevant.

I would not listen to that advice. I always seat and crimp into the cannelure or crimp groove. There are numerous reasons for this.
1. Prevent bullet jump and tying up the revolver cylinder.
2. Some powders prefer a solid crimp.
3. Prevent bullets from being pushed further into the case if shot in a lever action.
4. Ignoring the cannelure on a jacketed bullet and applying anything above a small amount of crimp requires a lot of pressure and will often times result in bent cases.
5. Ignoring the crimp groove on cast bullets will result in ring of lead being displaced and will cause problems.
There are reasons bullets have a cannelure and crimp grooves. If you look at any reputable load data it will list the OAL they used and at least 75% of the time that doesn't match the SAAMI max OAL.
 
I seated the 38 spl bullets for a C.O.A.L. of 1.550"
why?

And I'm being serious. Why did you load to the listed max COAL when there was no need, nor point?

The listed max length with bullet numbers are not "you must load to this" things, they are "don't go over this" things.

Loading "long" (to max or even beyond) in certain rifles to get bullets to the lands or just off them, simply doesn't apply to pistols that aren't shooting rifle cartridges.

Seating to the cannelure, whether you crimp or not gives a consistent depth of bullet in the case, and will always put you at or below the industry standard max length. Bullet designers figure this when they place the cannelure where it is, on each different weight & style bullet.

Now, there are combinations of bullet and case and firearm that are not compatiable, but they are rare with components of modern design.


My question here is why did you load the .38s to a set length, and not to the cannelure? With the .357, loading to the cannelure gave you the max length (and not over) in this case. Loading a different maker's bullet to the cannelure (same weight) could give you a different, and most likely below max length.


You can forget the cannelure altogether for .38 Specials.

You can, in a very few select firearms. If you aren't using one of them, its a barking stupid idea, and if using a tube mag gun, it can be DANGEROUS!!!

I can shoot completely uncrimped .38s from my T/C CONTENDER, all day long without any issues. I have tested 158gr .38s (850fps) uncrimped, fired from a S&W M28 (N frame, heavy revolver) and bullet jump is about non existent. The SAME ammo, fired from a Colt Agent (alloy frame snub nose, a light revolver) and bullet jump was significant. Not quite to the point of typing up the gun, but the bullets were "pulled" out of the uncrimped cases, 1/3 or so of their length. Even a light roll crimp prevents that.

As mentioned, ammo that will go in a tube magazine NEEDS a crimp, so bullets won't be pushed back into the cases, raising pressures possibly to dangerous levels.
 
MSD,

4.4 grains of Unique


reddog,

I will experiment with seating to the cannelure then compare to the original rounds. You say plated bullets do not have cannelures. I disagree because my Frontier bullets have cannelures.

Nick,

what you say makes sense. Thank you.


LE28,

these will be used in a lever gun. I understand about the purpose of a cannelure in tube fed gun.
 
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44 AMP,

I loaded to 1.550" because I have a chart on my wall with COALs for the calibers I load. I failed to look at the other cartridges I have loaded in the past for this same bullet, which I just did. They are seated to the cannelure for an overall length of about 1.352".
 
The COL depends on the bullet profile. There is no universal number. Sharing COLs without bullet context is not useful. The better number is what is the Max COL. Everything else is just crimped in the groove.
 
As long as it is "cowboy" level loads, not all of which are bunny farts, crimping 38 Special to a long COL rather than in the groove works routinely in cowboy action, tube fed rifles chambered for 357 Magnum. The guns generally require a longer COL for 38 Special to get the ammo to cycle reliably.The dies create roll crimps, which are set to make a bite into the lead, securing the bullet for any mild recoil inertia. I prefer to use 357 cases instead, but it is far more common to run a custom 38 round in both pistols and rifle, same load. More serious pressure and velocity levels for other purposes would be a different consideration.
 
Hint for a newer reloader. Seat your revolver bullets to the crimp groove or cannalure and disregard book OAL for now. Not familiar with Frontier bullets, but assume from the website, they are plated. Normally I don't recommend a plated bullet to new reloaders as they are neither a lead bullet or a jacketed bullet with unique needs/methods. But since your bullets have a cannalure, just seat to the cannalure, disregard book OAL, and do a work up starting with starting loads. You will be safe... K.I.S.S.
 
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