Hornady Leverevolution case length and safety revisited

[DWalt]

There has been some earlier discussion of the safety of firing Hornady Leverevolution (LE) ammunition in .35 Remington in Model 8 and 81 rifles. At this point, there is no reason to believe that LE ammunition presents any more of a safety hazard than any other factory ammunition, as, (a), Hornady has allegedly said it is perfectly OK to use their ammunition in the 8/81, and (b) in any event, the Hornady loads would have to produce chamber pressures at or below SAAMI specifications, or else advertise to one and all that their ammunition was unsafe to use in certain rifles - and no such warning has been provided - in order to avoid product liability lawsuits resulting from personal injuries or gun damage resulting from its use.

However, there was one more issue, namely is it unsafe to use Hornady LE cases for reloading, using convertional bullets? I did some internet research to discover exactly what the LE case issue is. What I found was essentially the following:

1. LE cases are typically shorter than standard cased by 0.16 to 0.18" (all calibers)
2. LE bullets have a sharper and longer nose profile vs a conventional RN bullet.
3. As a result of the longer nose of the LE bullet, it is impossible to put a crimping cannelure in the same position as it would be on a conventional RN bullet. In order to have the cannelure on the cylindrical shank of the bullet (where it must be), the cannelure must be moved further back from the nose than would be the case with a conventional bullet.
4. In order to preserve the same cartridge overall length (OAL) and to allow case crimping into the lower cannelure position of the LE bullet, the LE case must therefore be slightly shorter.

In summary, the factory LE cartridge has the same maximum OAL as any other factory cartridge of the same caliber and bullet weight, but the LE case must be shorter to match the case mouth to the lower position of the crimping cannelure of the LE bullet.

What does this mean for reloaders who have LR brass? Actually, nothing at all, at least for .35 Remington reloads intended for use in the Models 8 and 81 using conventional RN bullets. This is because there is no need to crimp the LE case mouth into the conventional bullet jacket cannelure, as the 8/81 has a box magazine, not a tubular magazine. There is no safety problem in reloading LE cases normally with conventional RN bullets. Just ensure the seating die is set to achieve the normal maximum cartridge OAL, and don't worry about not crimping the case mouth into the factory bullet cannelure (which will now be slightly above the case mouth), as crimping is unnecessary for use in the 8/81. Loading a conventional RN bullet in a LE case in such a way as to allow crimping of the LE case mouth into its cannelure would result in slightly reduced powder space, and could possibly result in slightly higher chamber pressures, and should be avoided, as the extent of the chamber pressure increase is not known. In fact, it may not be possible to crimp LE case mouths using normal unmodified .35 Remington seating dies due to the shorter case neck, because the shortened LE case cannot be inserted to the neck crimping portion of the seating die.

Therefore, much ado about nothing, so long as the same factory maximum cartridge OAL is preserved when reloading LE cases with conventional bullets. Don't throw away those .35 Remington LE cases just because they are a little shorter, at least if you are reloading for a Model 8 or 81.

[J. Riekers]

The problem with reloading is with the powder charge in the shorter brass. If you seat a bullet to the cannelure you are taking up more case capacity in the shorter brass, potentially compressing the powder depending on the load. If you seat the bullet out so the groove is above the short case you will have less bullet in the short case. Again, the issue is case capacity. In the later, your charge may not fill the case to the proper capacity percentage, thereby totally changing the pressure. A direct result of the low density load is a dramatic change in velocity and inconsistency. Bullet lengths differ among brands and styles and among weights too. There is no way to put a bullet of a different length in the LE case with a powder charge that would compliment that bullet and a standard length case - and not have a dramatic effect on pressure and the overall loaded cartridge performance. Even in a conventional standard length case there are different loads for different brand, style and weight bullets for this reason.
On the topic of crimping, I'll share my observations and research on this too. If you are using your 8/81 for hunting it will inevitably get loaded and unloaded several times in one trip, sometimes several times in one day. If a cartridge gets chambered 4 -5 times, maybe more or maybe less the bullet can creep out a few thousanths. I've tried it purposely and measured them. The bullet, neck tension given from your die and even the brand of brass will affect how long it will take to get bullet creep, if at all. With Remington brass that has been full length re-sized, chamfered and deburred and a smooth shank bullet like the Speer 150gr BTSP and NO CRIMP the bullet will start to creep out after 4 chamberings more than half the time per cartridge. A Lee factory crimp die, or a roll crimp from other brand dies can be used with or without the groove. This eliminates the bullet creep from chambering and ejecting a cartridge repeatedly. On another note, my chronograph shows a particular load without the crimp had a 66 fps spread. The exact same load with the crimp yielded a 34 fps spread. While not required or mandatory, I think a crimp has its benefits, especially for cartridges in 8/81 that might be loaded and unloaded and moreso in the 300 Sav than other calibers. Back to the LE ...
There are only two ways to safely reload the Hornady LE cases and get a consistent cartridge as a result. The first is to use the Hornady FTX bullet that is designed for the LE case with load data that is intended for the case/bullet combo. The second is to measure the water capacity in grains of the brass to determine capacity, then measure the bullet length and the length of bullet that will be inside the case of the bullet you intend to use. Apply the information to a program like QuickLoads and it will tell you the charge/powder/pressure/velocity.
I've studied this quite a bit with Mike Rintoul, the owner of Grizzly Cartridge Company. We used his pressure barrels and computerized equipment and programs in researching this. Admittedly, we did more testing with 30-30 and 45-70 than other calibers but we tried a few of every caliber where there is a LE version that has short brass. Using a long bullet seated to the groove is the biggest problem, but seating out a bullet and creating empty space in the case caused some issues too and the change in pressure and erratic performance were notable.
Im open to comments, suggestions and personal experiences but for now based on my research I will respectfully disagree with you on this issue.

[DWalt]

Please re-read exactly what my posting says. I am not advocating seating a conventional RN bullet crimping cannelure to the mouth of the LE case - just the opposite. Cartridge OAL is cartridge OAL, no matter the case neck length, and loading a conventional bullet to maximum OAL in a LE case is exactly the same as loading the identical bullet to the same maximum OAL in a Remington or Federal case regarding powder space. The powder space will be identical in both instances. There will be no powder compression. The ONLY difference is that the conventional bullet's cannelure will be a little ahead of the case mouth in a LE case, while the cannelure will be at the case mouth with the Remington case. A 0.16" difference in neck length (and that's all this is about) will make no detectable difference in chamber pressure IF both reloaded rounds have the same OAL. This assumes that the case wall thickness and internal base dimensions of the LE case are the the same as for a case from any other manufacturer, as that's the only thing that could possibly affect the case capacity to the base of the bullet.

Do you have verified laboratory pressure gun data showing that the peak chamber pressure from firing a .35 Remington LE case reloaded to maximum OAL using a conventional bullet is any different from exactly the same load at the same maximum OAL using a Remington or Federal case?

[J. Riekers]

After re-reading your first post and your second I think we are agreeing to an extent. What we found with the shorter length brass LE cases is that they require a crimp in order to have a consistent load. In a micro-scenario, the primer pushes the powder forward before it reaches thermal critial mass and ignites. That micro-moment starts moving the bullet forward. This causes and erratic burning rate since some powder is still burning as it leaves the case and enters the barrel. This is particularly noteworthy with double deterrent powders (like LeverRevolution). The folks at Alliant and also at SMP, the actual manufacturer of the Alliant powder told me there needs to be high volume case powder and no pre-mature bullet movement so the powder coatings cause properly timed ignition. While it would not be particularly dangerous, it will create a wide variance in velocity and consistency as well as a variance in pressure. Our testing shows an average difference of 4600 psi per load when Remington brass is compared to LE brass. While that is not detrimental unless you are at a max load, the variance of pressure was noteworthy with the difference running +2100 psi to +6700 psi in the LE brass using conventional bullets seated to normal OACL. A lot of what we said is the same. I am disagreeing with you regarding the need to crimp. I think the crimp creates more consistency as far as pressure and accuracy of the loads, and can be useful if you load/unload your 8/81 over and over. I am also disagreeing that it is "much to do about nothing" because the proper overall length, type of powder and crimp, or lack of will not get the utmost performance out of the loads and with the slilghtest bit of carelessness can create problems. Thank you for allowing me to participate in this spirited discussion. I think your points are well intended and laid out well. I hope I have merely added some detailed information.