Cratering and Smoke from reloads

K

Kevin1996

Inactive
I recently started reloading, my first cartridge being 30-30win. I seem to have a couple problems (or at least they seem like they could be) with my loads.
1. Cratering of primers
2. Grey smoke on higher loads

I made up a batch using 2 sources; the Hornady reloading book and the Lyman; Both being the newest versions. the batch contained 10 reloads using the Win 748 powder. Two at 31.9 grains, two at 32.0 grains, two at 34.0 grains, and up to 35.9 grains. Each has extremely similar primer indents and the 35.0 and 35.9 loads created a lot of grey smoke. Here are some pictures to give an idea:

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I was using CCI large rifle primers No. 200 and as I said, Win 748 powder that I had just bought. Also, I trimmed every case at or slightly shorter to the trim-to-length. I also made sure each bullet was at the recommended OAL (over-all length). I used these in my Winchester model 94 made in 1968. Each case fed and ejected with ease, also no apparent extraction marks. The cases were varied of hornady, Winchester, RP, Federal as apparent in the pictures. Every bullet was made with a lee 'factory crimp'. I don't believe they were over-crimped. This is how each were crimped:

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Also, it should be noted that the bullets were copper plated 150 gr .308 diameter bullets from xtremebullets.
The data in the Lyman states for 150gr jacketed bullets w/ 748 that starting load is 32.0gr and max is 36.5 gr.
Hornady manual states that starting load is 32.0 gr and max is 38.9 gr.

If I can provide any more information possible, I will try. Please help to let me know if this is something I need to take caution of or if it can be ignored.

I also have heard if the firing pin hole is slightly too large, it can cause something to mimic cratering and/or the firing pin not hitting hard enough.
 
I don't know for sure, but the plated bullets are generally a lower velocity proposition. Do you know for sure whether the ones that smoked like that made it to the target?

If I were to guess, I'd say that the plating failed and the bullet "disintegrated" as it left the muzzle. I've seen similar happen with fast twist AR's shooting lighter, 45 grain bullets. There is a puff of smoke down range as they fly apart.

Good luck diagnosing the issue. As part of your investigation, you might try a few traditional jacketed bullets to see how they hold up?
 
I suggest you look in the barrel for fouling before firing anything. It may be lead fouled. How were the targets?

David
 
Might be shooting the plated bullets a little too fast, I was under the impression that plated bullets should be treated like lead bullets and need to be loaded accordingly , I'm often very wrong and often off base though.
Nice pics by the way...:)
 
You are running those "Plated" bullets way to fast.

From X-treme.

Our Copper Plated Bullets can be run at mid-range jacketed velocities or higher end lead velocities. We recommend keeping velocities to less than 1500 FPS (Feet Per Second) and using only a light taper crimp

Any velocities over 1200 FPS we recommend either our Heavy Plate Concave Base or Hollow Point products for superior accuracy. We recommend keeping velocities to less than 1500 FPS (Feet Per Second) and using only a light taper crimp

http://www.xtremebullets.com/Bullet-Load-Info-s/1952.htm
 
Agree with stubbicat, you are pulverizing those plated bullets.

Get some real jacketed bullets or load plated like cast.

Your firing pin indents look strange but the primers are not a bit flattened, you are not likely over pressure and you are within book load limits.
 
Thanks for all the replies everyone! I should have researched on the website for the bullets that I bought. I had thought the copper plated bullets were the same as fmj, but apparently not.

According to the Hornady load data for 150 gr bullet, the velocities were well over the 1500 fps limit. I am at this point almost certain that the cause of both issues were the bullets.

Since there isn't any load data for 150 gr lead bullets (in my books), I will try to acquire fmj bullets and see how the results turn out.
 
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So they want you to keep the velocity below 1500 fps.

I have quite a few manuals but no loads below 1500 fps. At this point perhaps your bullet manufacturer can give you a load.

I found on line ( Oregon Trail bullet Co.)

They recommend Unique or Trail Boss powders.
 
I have been doing some research on new bullets with fmj, I have found a few 110 gr that are round nose. Only thing is not sure if I totally trust round nose on a tube fed high recoil gun. I want to keep the bullets as cheap as possible considering they're just for plinking right now.
 
My old pre. 1941 model 94 Win. had what I thought was a loose head space that I thought gave some odd looking cases. I loaded them light and stayed with the 150Gr. bullets designed for the tubular magazine.

Normally I thought in a tighter bolt gun cratering would mean HOT load. Although your primers aren't even flattened that indicate pressures are not high. Are those primers setting above the head stamp? Also are the crater peaks flattened? Those are mighty od looking primers to me.
 
Longshot4-

I made sure all primers were set below the head stamp. All the primers look as though they have no flattening, and the craters don't seem to be flattened at all. It's very odd, but I will try FMJ and test it out to see if there's any difference.
 
Plated bullets won't make the same velocities as jacketed, your loads are shearing off the plating. Also use flat points in a tube magazine, or the new plastic tipped Vmax.
 
I bought 100 bullets of 110 gr fmj round nose and 100 bullets of 150 gr fmj flat nose. My lyman book has the same 110 gr round nose (exposed lead tip) for load data. I have read that round nose exposed lead is fine to use and manufactures of 30-30 even sell that. When they come in, I will try loads with each and share my results.
 
What is going on, at the instant of firing the soft swaged plated bullet is upset by the pressure and fills the bore completely, the plating is not a lube and is of no help. A cast bullet is of alloy and much harder than the pure lead, with lube grooves.

When the bullet fills the bore completely the pressure goes up sky high cratering the primers. Who knows how fast that slug of pure lead is going.
 
Followup question: Do the primers in factory ammo also look like that? There is no flattening indicative of thermonuclear pressures, but I agree the indentations do have a ridge in them.

Cratering as I have ever seen, is where the primers are flattened at the edges all the way from the firing pin indentation, to the edge of the primer pocket, and across the surface, with a ridge at the junction of the firing pin indentation and the flattened part of the primer. It is caused by the primer flowing back into the firing pin aperture/hole in the breach face. In these cartridges there is a strange ring which appears to be down inside the indentation from the firing pin, which if I were to hazard a guess, is caused by an anomaly in the tip of your firing pin. The location on the cap where cratering indicative of high pressures appears, shows no such sign. There is no ridge around the primer at the point where the firing pin aperture would interface with it.

I agree with you that the ridge down in the primer indentation is unusual, but I don't think it is indicative of excessive pressures. I say that because the remainder of the primers are nice and rounded over where they meet the primer pocket, not flattened out. Does your rifle have a rebounding hammer?

But it is important to note that while your photos are very good, I am not there to inspect the cases, and I could be completely off base and wrong altogether.

Another question: Did the bore clean up easily after shooting these rounds?
 
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Your cratering may be due to an over sized firing pin hole or an under sized firing pin. Cratering by itself may not mean excess pressure. On the other hand if you ever get flat primers in a 30-30, you are way beyond a safe load.
 
stubbicatt-

I cannot say if factory ammunition does this since I already resized and deprimed my old factory shot ammunition and hadn't looked. I need to buy a new box of factory ammo to see. Also, my gun actually seemed to clean up easier than normal. No lead fouling like some have been stating. I clean my gun after every shooting so the gun being dirty was not an issue.
 
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