Speer HBWC Velocity?

[efelien]

Hello,
I loaded a few Speer 148 gr 4618 hbwc (357 mag) using 6.4 gr Unique. Loaded them flush with a mild crimp over the top. Then I shot 3 through my very old Chrony Model F (with the cardboard holes to shoot through). I got 1812,1605,1726 fps for the three. I'm new at pistol reloading, and I'm wondering if this much inconsistency is normal, or what might be causing it, and also, do you think that I'm pushing these lead bullets too fast? I use an RCBS Uniflow measure, and weigh occasionally. The weights seemed always to be very close to the same. (not one mm above or below center on my 5-0-5 scale.) And they seemed very comfortable to shoot.

 

[zxcvbob]

Don't use HBWC's for a hot load like that! You can use DEWC's, but you'll get some leading. Where did you get that load data?

 

[NCsmitty]

There is little chance that your velocities mentioned are correct. I would guess that they are not over 1100fps with an actual 6.4gr of Unique, or at least shouldn't be.
Verify your chronograph with some 22 rimfire of a known velocity area.
It's best to keep HBWC under 1000fps for a couple reasons.



NCsmitty

 

[Steve C]

Check you cases to see if you didn't leave the outer ring of the bullet in the case and check your barrel for the same.

Your load of 6.4grs is the maximum for a "non target" 148gr wad cutter listed by earlier Alliant data but that's for a solid base bullet, either bevel base or double ended. The maximum listed for a "target load" is 3.3grs of Unique and would be appropriate with the HBWC.

Never use heavy loads with HBWC's as the pressure will expand the bullets skirt either in the case or in the barrel so tight it will either tear off OR blow the center out of the bullet. HBWC's are traditionally used in the .38 spl for use in .38's and .357's and their maximum velocity is right around 800 fps.

If you where blowing out the center it very well could be that your velocities of the partial bullet was that high.

 

[NVMM]

All above info is correct.
What was the distance between muzzle and chrony?

 

[rcmodel]

Speer 148 gr 4618 hbwc (357 mag) using 6.4 gr Unique.

Cease & desist immediately before you damage your gun!!!

That is a soft-swaged lead bullet designed for low pressure and target velocity of 800 FPS or less.

Speer does not even list a Unique load in .38 Special with it.

A hollow-base wadcutter should never be used with high-pressure loads for the reasons mentioned in the other posts.

rc

 

[noylj]

I found that just getting above 800 fps with a HBWC produced twice as many holes in the target. Thank god that most guns are built strong.
Were these bullets loaded with the hollow base as the front of the bullet?
Check barrel for bulge.

 

[ReloaderFred]

Your bullets were separating, with the blown out nose of the bullet going through the screens first. I've seen this before when a HBWC was loaded hot and produced two holes in the target, one from the nose and the second from the skirt.

Also check your barrel for excessive leading. The person who was shooting the rounds I witnessed couldn't even see his rifling after about 18 shots.

If you want to shoot HBWC bullets, use Bullseye, Winchester 231 or Hodgdon HP-38, in small doses, according to published data.

Hope this helps.

Fred

 

[efelien]

Wow, thanks for all the answers. I didn't load the bullets backward, and when I shot some at my 1/2" thick plate steel target they made a perfect round depression, much deeper than any other. I'll absolutely cease and desist with that load.

 

[MrBorland]

This bullet was designed to be very accurate, but at much lower velocities, as others have noted. As long as you have them, then, try loading some up for accuracy.

I use the very same bullet with a light load W-231 or bullseye in a .38spl case as my target load. It chronos @ 710fps and is a very accurate target loading. Shooting unsupported, double action, I can print sub-1" 5-shot groups using them:


For the record, you asked if your inconsistent velocities were normal: Readings of 1812, 1605 and 1726 fps, give you a 6% standard deviation, and while others can chime in, SDs from my test sessions are typically under 1%. I'd personally consider anything above 1.5% too high for my taste, especially when it's my own target ammo that's being tested. YMMV.

As others noted, you're likely damaging the bullet at this velocity, which is at least partly why you're getting inconsistent velocities.

 

[rcmodel]

At this point, I would give the barrel a real good cleaning with a bronze bore brush & solvent, then inspect for a ringed or bulged barrel.

At the very least, it is sure to be very badly leaded from shooting those soft-swaged HBWC bullets at nearly twice the design limitations.

rc

 

[efelien]

Thanks loads. I pulled the remaining bullets (not a fun job with an inertia puller). I only shot six rounds, didn't see any leading, but I did bronze-brush the barrel and chambers (GP-100 6"). I have Bullseye and 231 powders, and I'll do more reading before I load any more...

 

[NVMM]

2.7 grains of Bullseye... You'll like it.
Your target should look just like MrBorland's.