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Hansj
02-26-2011, 05:33 PM
I partially seated a Sierra 125g FN HP bullet in an empty case that I had already trimmed to 2.030" and chambered it to check chamber depth, I am .050" short of the cannelure and measure COL 2.488".

I know it is important to crimp on the cannelure but as I understand it the bullet should be either in contact with the rifling lands or close to it (one of my buddies says .010 short of the rifling is ideal). What advice is there out there? Should I trim my cases longer (or rather not trim them as short:razz:) to engage the cannelure and lengthen the seated COL to engage the rifling? I only have one box of these bullets right now but I would like to give them a fair shake to see what sort of potential they have. Oh yes, the rifle is a Marlin 336.

fryboy
02-26-2011, 07:20 PM
the lever action rifle is a far different approach than a bolt action rifle , and yes especially with any kind of tubular action the bullet should be firmly crimped or no matter what you set the length to it can and will change under recoil and during the loading process and can cause jams and dangerous pressure spikes , as for your buddy .... i dont know the guy but hearing this upon lever actions leaves me to question his ummm "expertise" , having stated that , sierra's fifth edition list a length of 2.420
i actually like this bullet and have used unknown numbers of them , i prefer a heavier constructed bullet for deer if using this caliber ( they also work fair in a sks/ak ) h322 and imr 4064 are two of my fav powders for it , i also use it in my 30 herret where the lower velocity makes it less frangible on game , in the 30-30 i have always set the bullet to the cannalure but with a lee factory crimp die you can sort of crimp it where-ever you want but it will distort the bullet somewhat
BTW ? the variable of setting any distance off the lands is highly dependent upon the rifle and the bullet - IMHO boat tails benefit the most from this , some rifle/bullet combos prefer more some less
as for trimming ....as long as they arent too long uniform is best as it helps impart a more uniform crimp , the 30-30 with it's relatively soft brass and shoulder angle tends to flow rather easily so checking lengths after every firing makes sense ( especially with loads in the warmer spectrums )

Hansj
02-26-2011, 09:24 PM
Thanks Fryboy, but can you elaborate on the advice I was given that the bullet should be seated .010" deeper than where it contacts the rifling? Why is this in your opinion a bad idea? Or should I just seat to the cannelure, crimp and call it a day?

As for powders I have IMR4064, H-335 and I might have some H-322 but I'll have to check. I was going to work with the former two in my testing.

fryboy
02-26-2011, 10:15 PM
h335 is also a decent powder but the other two gave me a bit better accuracy , of course all barrels do react differently , ww 748 is also a decent powder for this round , i would seat to the book in this caliber , the need for a crimp ad the crimp groove pretty much go hand in hand but there is a lil play with the groove albeit not much
as for the length off the lands ... on some chambers ( especially weatherby's with their notoriously long freebore ) it isnt possible to even seat close to the lands and some weatherby's are known to be very very accurate , in fact some of their vangaurds are advertised to guarantee shooting under a minute of angle ( not all there is a premium price on these ) also seating closer to the lands can raise the pressure so if i had a max load worked out and then extended my bullet closer to the lands much like seating too deep it could raise the pressure , in a bolt action rifle i'm all for experimenting with seating depths as one never knows until one tries but when it comes to tubular mags and heavy recoiling rifles the need for a crimp exist , some benchresters seat short and some actually seat into the lands , it again depends upon what the barrel likes but the caveat there is that they start small and work their way safely up , i've seen alot of guns that shoot worse with flat based bullets seated close to the lands and it honestly is much more common with boat tail bullets ( which they say need to engage the rifling sooner for their best accuracy potential to be realized even tho i havent always found that to hold true but they usually do have a sleeker ogive increasing the odds of not starting as true ), the lever action also is a far far cry from being bench rest capable ( at least in the winchester and marlin platforms ) it also is a shorter range proposition and what would translate to being a tighter group at 600 yards in no way applies to this which is at best 150 yards or under ( especially with flat nosed or round nosed bullets )

Hansj
02-26-2011, 11:24 PM
Thanks again Fryboy, I think I will just seat to the cannelure and work things out from there. I am not one to max out a load just for the kick of it, I am interested in accuracy and my lever gun is for brush busting for deer or pigs. I also want my kids to be able to comfortably handle it as well.

Unfortunately I live in the Peoples Republic of California so it looks like we will be restricted to lead-free only statewide as of July 1st (for hunting), which limits my choices for bullets. That is the subject of another thread though. I am looking at the Hornady Monoflex for lead free but it only comes in a 140gr.

versifier
02-27-2011, 02:17 AM
Don't worry about getting the bullet up close to the lands in a lever action. It needs to feed and function first, and crimping it in the cannelure will get you where you want to be to start off and get your loads worked up. If you want an OAL longer or shorter than the cannelure allows, get a Lee factory crimp die and crimp it wherever you want. Get one anyway, roll crimps suck. 8)

If you want to play with seating close to the lands, do it with a bolt action or a single shot. The lever is a hunting rifle and it needs to feed and function reliably in the field, and when you start seating bullets way out, you're going to run into feeding problems when your OAL exceeds the length the action is designed to work with. It's fine if you're going to run it as a single shot and load them one at a time at the range, but if they have to feed through the magazine (i.e. you need a follow-up shot on a deer) it limits your maximum length not to what shoots best, but to what feeds most reliably.

For Sierra 125grFNHP bullets in the .30-30 I've always done best with either RL7 or 3031 in a variety of different action types: lever, bolt, & ss. YMMV. They have performed quite well even on large deer (over 200#) out to ranges of 200yds or so around here. I like them because they shoot flatter than 150's and especially 170's. For a jacketed large game bullet in the .30-30, I don't think there's a better choice out there.