Concerns about 38 Special Revolver Reloads in a Rifle

[Adventurer 2]

I am feeling mentally challenged right now and want to find out if I have been doing anything else "unsafe" for the last few years. I just found out that I probably shouldn't have been using my rifle 357 mag reloads in a revolver. The load is too light for the revolver.
Are there any concerns with using 38 special revolver reloads in a lever action, Marlin 1894C, rifle?

 

[bluetopper]

A rifle round too light for a revolver???
I don't think you've been doing anything wrong whatsoever. Keep doing what you are doing and have fun.

 

[SLOMountaineer]

Well, if you purchase factory .38 it isn't going to be a rifle round and there are thousands of those .38 lever actions owned by people who don't handload.

What safety concern did you have?

 

[Adventurer 2]

The problem with light loads of H110 or Winchester 296 is that they don't get up to high enough pressure to burn well. That is what makes them "dirty". In a revolver, because its cylinder gap vents pressure, it is possible for the light loads to essentially quit burning early and leave a bullet lodged in the barrel. That (along with the dirty powder residue) is only a pain in the a** IF YOU CATCH THE SQUIB AND CLEAR THE BORE BEFORE FIRING ANOTHER ROUND. The hazard comes from the potential for not catching the squib and firing another round into the obstructed bore.

Older reloading manuals tended to show much reduced loads for H-110, even when they carried warnings about not reducing WW-296 at all. (The two powders are alledged to be nearly identical products of the same factory.) Now that Hodgdon has acquired Winchester Powders, they have started showing identical load data for H-110 and WW-296 (even though previous data almost always showed H-110 to be a tad slower than WW-296) and they now say neither should be reduced by more than 3%.

SL1 posted the above - I think he is right. 15.8 grains of H110 and a 125 grain jacketed bullet is a good load for a 357 magnum rifle. It was the lightest 357 mag load I shot in my revolvers but under what the loading manuals state.

 

[Adventurer 2]

My concern is I don't know what I don't know. I am wondering if there is anything to be concerned about with shooting reloaded revolver 38s in a rifle.
I have never seen data for 38 reloads for a rifle. In 357 magnum the loads, using the same bullet, are of a smaller charge than for a revolver round.

 

[zxcvbob]

I've played around with .38 Special data in QuickLOAD software, and the most ridiculously light load anyone would shoot in a revolver (2.0 grains of Clays with a 125 grain jacketed bullet) has a muzzle velocity over 100 fps faster from an 18" rifle barrel than from a 4" or 6" pistol.

 

[SL1]

Speer warning on min 357 Mag loads in rifles

Adventurer 2,

You wrote "In 357 magnum the loads, using the same bullet, [the rifle loads ?]are of a smaller charge than for a revolver round."

I am not sure what gave you that impression. Are you using two different data sources for the two different guns? If so, I can see how you might get the impression that max or min charges are different in different guns, because data sources do vary some. But, especially for max charges, they should be the same (assuming identical bullet construction) because there is a SAAMI pressure limit that must not be exceeded in a test barrel with a standard configuration.

Minimum charges might be a little different, due to things like the cylinder/barrel gap venting pressure (after the peak) in revolvers, longer barrels in rifles, etc.

Because you asked, I should to tell you that the new Speer Reloading Manual #14 does contain a warning regarding minimum charges for 357 Mag loads in rifles (page 617). It reads:

"Do not use loads less than the minimum charges shown. Small charges of powder may not be sufficient to push a jacketed bullet down an 18-inch barrel; a dangerous bore obstruction may result."

I had never seen this before (or elsewhere).

After reading that, I compared the minimum charges for 357 mag loads between their rifle and handgun sections and find they are identical except for a couple of cases where there was a 0.5 grain difference (one higher; one lower). So, it does not suggest that their data range is really different for the two types of firearms. Their minimums are higher than most other data sources, though.

But, you asked about 38 Special loads in your rifle. The Speer warning would suggest that those loads might not push a bullet out the barrel, because they are typically less than 357 Mag start loads.

Frankly, that warning seems very strange to me. I note that they do not repeat it for their 44 Mag rifle data. I also note that the 32-20 Winchester data in the rifle section of the same manual does not contain that warning, even though its max charges produce only 16,000 psi (less than a 38 Special round), and they are pushing a bullet with a similar sectional density down a longer barrel length (22") using the same powders as the 38 Special in proportional charge weights. That data is for a LEAD bullet, so bore friction would be lower than for a jacketed bullet. But, ammunition companies have been making 32-20 cartridges with jacketed bullets for years at this same pressure level, so I don't see why those bullets would not stick in a barrel if the 38 Specials would stick.

So, frankly, I don't understand why Speer felt that warning was necessary for their 357 Mag rifle data. You could call Speer at 1-800-627-3640 or ask them the question in writing through their website http://www.speer-bullets.com/ . (I have found that manufacturer's technical personnel are more forth-coming on the telephone, where their lawyers don't get to review what they say.)

If it were me and I wanted to shoot lighter loads in my rifle, I would use my chronograph to measure the muzzle velocity of the loads that interested me, being careful to check that each test bullet actually left the muzzle before firing the next one. If slow bullets got anywhere near ready to stick in the bore, I would expect to see that in erratic muzzle velocity readings. Since those are not good for accuracy, anyway, I would avoid using erratic loads, no matter what was causing the erratic behavior. Just remember, if you are blasting away in a cowboy action event or just for fun somewhere, the bore will be fouling and the friction will be going up. So, you do want margin for those situations where you are not so likely to be paying close attention to whether each bullet really did come out of the barrel.

Finally, with respect to better powders than H-110 for less-than-max loads with 125 grain jacketed bullets, here is some data for you from the new Speer manual:

Blue Dot: start 11.5 grains (1729 fps rifle / 1252 fps revolver); max 13.0 grains (1916 fps rifle / 1333 fps revolver)
2400: start 16.5 grains (1851 fps rifle / 1335 revolver); max 17.5 grains (2019 fps rifle / 1409 fps revolver)
AA No.7 : start 12.0 grains (1588 fps rifle / 1045 fps revolver); max 13.5 grains (1770 fps rifle / 1134 fps revolver).

The mid-speed powders that I mentioned in a prevous post (Unique, SR-4756 and Universal) are not listed by Speer for use in rifles, but their 357 Mag revolver data for 125 grain bullets is as follows:

Unique: start 8.6 grains (1259 fps revolver); max 9.6 grains (1343 fps revolver)
Universal: start 7.5 grains (1148 fps revolver); max 8.2 grains (1200 fps revolver)

(Both of those powders are listed in their 32-20 rifle data.)

Velocities were measured in an 18" Marlin 1894 rifle and a 6" S&W Model 19 revolver.

SL1

 

[Adventurer 2]

SL1 thanks for all of your info.
I've only used my new chrono a few times.
I have reloaded without the chrono since 93 (38 and 357) and never loaded up to max charges. I usually worked up to the next from max charge and used that as my load in respective powder and bullet combination.
A few years ago an angry woman threw away some of my stuff, including reloading books and my laptop (with reloading information) disappeared. Since that time I bought a 357 Magnum lever action rifle. During the last year, I started reloading again. I bought a few new reloading books.
It is important to know the exact bullet and powder. In the Hornady, 7th Edition, book for 357 Magnum Rifle:
#35710 HP-XTP (125 grain jacketed .357 bullet)
H110 Start - 10.4 grains / 12.2 / 14.0 / 15.8 / 17.6 / Max 19.4
Same bullet for 357 Magnum Revolver:
H110 Start - 17.4 grains / 17.9 / 18.4 / 18.9 / 19.4 / Max 19.9
I can use the same bullet #35710 HP-XTP in 38 special loads. Those loads did not feel nearly as powerful as 15.8 of H110.

15.8 felt like a magnum in the rifle (better than any 38 special load) and that is the lightest 357 mag load I use in my lever. It also felt like a magnum in my revolvers (better than any 38 special load) and it is the lightest 357 mag I shoot in them. I am not going to use that load in the revolvers anymore. I will step up to the min level and look into the information you have provided. Thanks again.

 

[zxcvbob]

Do you have the H-110 or W296 powder already?

Alliant 2400, Power Pistol, or Herco, or Accurate #7 or #9 might be better choices and they will be cheaper to shoot.

 

[Unclenick]

zxcvbob,

Did you turn on the barrel friction feature when you ran the QL tests on the .38? Did you follow the straight case suggestion to increase the case volume 7% (opening info when you turn QuickLOAD on)?


Adventurer2,

You are correct that H110/296 should not be underloaded in revolvers. That 3% warning appears on the opening screen at Hodgdon's load site if you scroll down far enough. It is overly conservative, IME, and doesn't separate revolvers out (for legal reasons, I'm sure—you never know who will pick a load intended for one gun up and put it in another). H110/296 is the same powder. A Hodgdon tech verified that for me. I believe it is a St. Marks Powder (General Dynamics) product. It started life as a non-cannister grade powder for ammunition manufacturers. Hodgdon was the first to package it in cannisters for relaoders. Being what is normally a non-cannister grade powder, it has more lot-to-lot variation than you see in the blended cannister grades of rifle powder. That's why the manuals list loads that vary more than the 3% you recommended reduction limit. Their writers worked their loads up with different lots, then applied the overcautious 3% limit.

Light bullets will be more sensitive to the load reduction requirement than heavy bullets. Heavier bullet's greater inertia better swamps out variations in crimping and case dimensions and take longer to clear the case mouth and chamber throat, giving the powder more time to get burning. An objective lower limit percentage would be a larger percentage for heavier bullets than for light ones, but they like one-size-fits-all when it comes to instructing reloaders, thus to avoid memory errors.

In QuickLOAD, the two samples of this powder that Hartmut measured for the database (one of H110 and one of 296) had characteristics that produce about 10% difference in the peak pressures they calculate. That's lot variation. The two packages weren't from the same parent lot. The reason Hodgdon and, formerly, Winchester could get away with that is the powder produces low peak pressures relative to other powders producing the same muzzle velocities, so the variance stayed within safe pressure limits for the recommended loads. Indeed, Winchester, for a long time, had no minimum load and wanted you to use just their one load for each bullet type (jacketed and lead).

As to the .38's, if you use them in a tubular magazine, be sure to get flat nose bullets to avoid primer ignition in the magazine tube stack. Also be aware that the shorter .38 special case lets fouling build up ahead of the case mouth where a .357 case wants to go. Especially with lead bullets. That fouling, if it builds up enough and is not removed before loading .357 ammunition, can jam the .357 case mouths, raising chamber pressure. It isn't that hard to clean, but you need to be aware of it and be good at getting the lead out.

Nick

 

[SL1]

Hornady data

Adventurer 2,

OK, I see where you are getting the idea that revolver and rifle minimums are different. I think you are misreading the data a little.

I don't have the 7th edition Hornady manual, but I do have the 4th edition. It uses a format where it shows a range of velocities across the top (of the data for a specific bullet) and a list of powders down the side. I think your edition uses the same data format. Most powders have data starting at the lowest velocity shown, but that does not mean that lower charge weights are not acceptable. A few powders don't have data for the lowest velocities, which does indicate that they should not be reduced further than the lowest charge given.

Comparing the Hornady data for the 357 Mag in rifle and revolvers in the 4th edition indicates that there is H110 data for the lowest velocity shown in the revolver section (19.3 grains giving 1450 fps from a 8-3/8" S&W model 27) but they do not give any H-110 data for comparison in the rifle section. Interestingly, the max in the 4th edition is 20.6 grains for 1650 fps. So, the data seem to have changed between our editions. The difference between your maximums and mine may be due to the change from CUP to PSI in the SAAMI standards. The difference between the two maximums (rifle and revolver) in your edition is probably due to the selection of powder charges that give the velocities indicated, rather than the absolute max values, which would not get to the next velocity increment in the data tables.

For minimums, pay attention whether the data goes down to the lowest velocity shown, or stops at a higher value. If it does not stop, it simply means that data for lower loads are not provided, rather than they are not acceptable. There probably is some value below which those powders should not be loaded, but that is not provided by the data in this format.

Even data that shows "start" and "max" loads is usually not intended to indicate how low charges can safely go. That format typically assumes the reloader is interested in maximum or near maximum velocity. So, the "max" is the value that is never to be exceeded and the "start" is how far to back off in order to give enough margin to assure a safe first shot in any gun chambered for that cartridge. Most "start" values are simply 10% reductions from "max" values.

Warnings on minimum loads are usually provided in the text for specific powders and/or bullets where appropriate. As I wrote before, limits on WW-296 minimum loads have been around for years, and similar limits on have recently been provided for H-110 (3% less than max for each).

Cowboy action shooting recently has led to a lot of people using super-light loads to gain competitive advantage in a game where the only thing the bullet has to do when it gets to the target is make a hole in paper. There have been some gun blow-ups due to bullets lodged in the barrel. WHY those bullets lodged in the barrel is not really known. Some people blame it on cartridges that failed to get powder when loaded, so only the force of the primer was driving the bullet into the barrel. That will always stick a bullet in your barrel. Others blame it on too-light charges. Who really knows? It does give lawyers something to write about, though. So, I expect we will be seeing more cautions as time goes on.

SL1

 

[zxcvbob]

Did you turn on the barrel friction feature when you ran the QL tests on the .38? Did you follow the straight case suggestion to increase the case volume 7% (opening info when you turn QuickLOAD on)?

No, and no. I'll have to read up on that when I get home tonight.

BTW, the QL predicted values have been remarkably close to what I've seen with a chronograph, but those have all been hot loads; I haven't tried measuring any wimpy loads.