PDA

View Full Version : Front driving band jammed into the lands. Ok or not?



CamoWhamo
11-14-2019, 12:40 AM
The rifle is a new to me Marlin 336 in .35 Remington with a Microgroove barrel.

I just cast up a few different bullets to test fit before loading some ammo.

All of them show signs of the front driving band touching the lands.

The pic shows an Accurate mold bullet with a front driving band that is .060".
It is sized at .359

I also tried the RCBS 358-200-FN and got the same thing, just a bit shorter because the front driving band is thinner.

Would these be safe to shoot?

I'm planning on using 18 - 20gn of Alliant 2400 which should get me around 1700fps.

251223

bmortell
11-14-2019, 01:24 AM
safe, I would say yes. people shoot jacketed with the jacket pressed to the rifling, and Ive shoot paper patch where they stay in the rifling if I unchamber them. so I wouldn't think its that weird to start out already in the rifling. especially if it takes little force to chamber them and make those little dents.

Walks
11-14-2019, 01:26 AM
I do it for My .38-55 Lever gun. It definitely helps accuracy.

Winger Ed.
11-14-2019, 01:31 AM
I do it with cast in .308, .30-06, and .45-70.

I've seen articles, and I think on a article thing in a older Lyman book
where they tell ya that you more or less have to do it with fat front ended 'bore riders'.

sigep1764
11-14-2019, 02:01 AM
I have read that seating into the lands can cause pressure spikes. When I was determining max overall length for my 270, I actually pulled a bullet dropping powder all over inside of the action of my rifle. Seating just a little bit deeper eased loading and unloading of the rifle and I didn't notice any change in accuracy between the two lengths.

44Blam
11-14-2019, 02:08 AM
That much touching is a little much - you might want to seat your boolit so it JUST touches the lands...

LawrenceA
11-14-2019, 04:06 AM
Seating on the lands does increase the initial pressure required to get a bullet moving which in turn is affected by rifling angles and bullet hardness. It can certainly affect accuracy but each gun is on its own. Just to confuse the issue if the rifling has basically cut through the first band then this will decrease pressure (like a muzzleloader. The work is done).
Generally touching or just off the lands gives best accuracy.
How much pressure do the books say you will get with this load? Is it a soft bullet? How does that compare to the rifles specs? (Marlins are 40,000 from memory).
Personally I would seat em deeper to just off then no reliability or pressure problems and well I can't shoot straight enough to note a difference on game.

Ramson222
11-14-2019, 04:27 AM
My experience has been pulled bullets, and high pressure. I recommend loading a dummy round then coloring the bullet with a black sharpie. The sharpie will make seeing the amount In the bullet is the lands easier. Just keep seating your bullet deeper until you a tiny line around the colored bullet, then seat a bit deeper just to be on the safe side.

Wayne Smith
11-14-2019, 08:56 AM
Only your rifle/boolit combination will tell you. Safe, yes. Accurate, only experience knows.

Texas by God
11-14-2019, 09:00 AM
Doing that, sooner or later, you will try to unload the chamber and the bullet will stick in the throat and your rifle action will be full of gunpowder and you will say bad words. Seat them to where you can easily cycle loaded rounds through the gun.

Sent from my SAMSUNG-SM-G930A using Tapatalk

ABJ
11-14-2019, 09:12 AM
Safe? yes. Accurate? Usually is with the right powder charge. I shoot a lot of lever guns and I would want it seated a little deeper so as not to put undo pressure on the lever. Another 1000th to 2000th deeper should be fine. I like them to touch and not engrave on lever guns. On bolt guns I like them to engrave.
I also noticed in the pic, it is not crimped. I would seat the driving band down into the mouth and crimp just enough for a tight grip on the bottom of the driving band. You do not have to crimp into the crimp groove. After looking at your pic real close you might want to try seating so the lowest engraving mark is right at the case mouth. It should close without resistance.

Tony

CamoWhamo
11-14-2019, 06:40 PM
I also noticed in the pic, it is not crimped. I would seat the driving band down into the mouth and crimp just enough for a tight grip on the bottom of the driving band. You do not have to crimp into the crimp groove. After looking at your pic real close you might want to try seating so the lowest engraving mark is right at the case mouth. It should close without resistance.

Tony

Correct, the case in the pic is not crimped. It's just a dummy round with old brass being used to check the bullet fit.

I made up another one with bullet seated deeper and crimped on the front driving band using the Lee Factory Crimp. It looks good and seems strong enough. I'll make a few rounds and watch closely for any signs of the bullets getting seated deeper under recoil.

251263

Conditor22
11-14-2019, 07:04 PM
I read somewhere that you get the best accuracy when the boolit is .009 - .011 off the lans, haven't tried it yet

Larry Gibson
11-14-2019, 07:09 PM
I read somewhere that you get the best accuracy when the boolit is .009 - .011 off the lans, haven't tried it yet

I have. Not found that to be the case. Best accuracy with cast bullets in rifles has been with the drive band seated firmly into the lands..... just as in the OP's picture.

44Blam
11-15-2019, 12:31 AM
Doing that, sooner or later, you will try to unload the chamber and the bullet will stick in the throat and your rifle action will be full of gunpowder and you will say bad words. Seat them to where you can easily cycle loaded rounds through the gun.

Sent from my SAMSUNG-SM-G930A using Tapatalk

I've done this. Sure enough, I said some bad words.

mehavey
11-15-2019, 08:35 AM
Safe? At normal cast-limited pressures, probably just fine.
Accurate ? Most likely as good or better as any other seating w/ that load combination.
Troublesome ? Could pull the bullet/spill the powder upon unloading -- most likely not, however, at the engagement first shown.

FWIW: Moderate simultaneous Roll-crimp into the driving band works just fine w/ the seating die. No shoulder bulge if you don't orangutan it. All you need is enough 'dig-in' to anchor the bullet from being pushed further in.

PPS: How hard is your alloy w/ that microgroove? Contrary to conventional wisdom of softer-is-better w/ deep Ballard rifling, somewhat harder is needed to hang onto the microgrooves.

Hickory
11-15-2019, 08:46 AM
Safe? At normal cast-limited pressures, probably just fine.
Accurate ? Most likely as good or better as any other seating w/ that load combination.
Troublesome ? Could pull the bullet/spill the powder upon unloading -- most likely not, however, at the engagement first shown.

FWIW: Moderate simultaneous Roll-crimp into the driving band works just fine w/ the seating die. No shoulder bulge if you don't orangutan it. All you need is enough 'dig-in' to anchor the bullet from being pushed further in.

PPS: How hard is your alloy w/ that microgroove? Contrary to conventional wisdom of softer-is-better w/ deep Ballard rifling, somewhat harder is needed to hang onto the microgrooves.

This is very good advice, it is what I do with my Marlins.

ABJ
11-15-2019, 10:25 AM
Cammo, That looks much better. You can afford a touch more OAL to where the driving band kisses the rifling if you want to. If those are used for hunting and group well then I would leave it like it is. Like Larry said, all things equal, engraved produces the best accuracy most of the time. Leverguns don't have the mechanical advantage that a bolt does.
Tony

Maven
11-15-2019, 12:54 PM
I have. Not found that to be the case. Best accuracy with cast bullets in rifles has been with the drive band seated firmly into the lands..... just as in the OP's picture.

Larry's correct about this even if you'll get a CB stuck there on occasion (as per TX by God), spill powder, say bad words, etc. (Don't ask....!) However, whether your particular rifle, CB, load is more (or less) accurate with the driving band (or nose if it's a bore rider) stuck into the lands, is easy enough to test.

Shuz
11-16-2019, 12:03 PM
Plus 1 to what Maven and Larry Gibson posted.

MostlyLeverGuns
11-16-2019, 03:45 PM
Accuracy should be good, probably better than off the lands when using boolits. Pressure should be OK with indicated load. Biggest concern is extracting live round and leaving bullet stuck in chamber, dumping powder inside action and rendering rifle out of action until bullet removed. It is unlikely that another round would chamber with a bullet stuck in throat but I suppose a real hammer mechanic could manage to load another round so two bullets were in front of the case. THAT would cause serious, maybe catastrophic problems if fired. Snugly into rifling GOOD, stuck in rifling on extraction, not so much. Breech seating in single shots is a whole other discussion.

mike69
11-16-2019, 08:58 PM
I'm using the Lee 358-200 in my Marlin 35 rem and can just feel it touching as i close the lever . It's cast from coww and using IMR 3031 powder sized 358 . Shot a nine shot group at 100 yards that was just about 2 inches .

bmortell
11-16-2019, 09:37 PM
whether a boolit would get stuck should be testable. if your normally gonna crimp a little test a few with no crimp. or if you don't crimp maybe polish a bit and oil the inside of a neck and see if it pulls in worst case scenario then you could have peace of mind in normal scenarios.

44Blam
11-18-2019, 02:28 AM
Accuracy should be good, probably better than off the lands when using boolits. Pressure should be OK with indicated load. Biggest concern is extracting live round and leaving bullet stuck in chamber, dumping powder inside action and rendering rifle out of action until bullet removed. It is unlikely that another round would chamber with a bullet stuck in throat but I suppose a real hammer mechanic could manage to load another round so two bullets were in front of the case. THAT would cause serious, maybe catastrophic problems if fired. Snugly into rifling GOOD, stuck in rifling on extraction, not so much. Breech seating in single shots is a whole other discussion.

I've had this happen where I had a boolit stuck in the barrel and I just used a cleaning rod to push it out - you could use a coat hanger or a stick - they're generally not stuck that bad. No big deal. With the action, I dumped as much powder as I could out and then I just shot the gun - stick powder will just break up and if it catches on fire it isn't a big deal because it isn't contained in a cartridge...

Conditor22
11-18-2019, 01:54 PM
I have. Not found that to be the case. Best accuracy with cast bullets in rifles has been with the drive band seated firmly into the lands..... just as in the OP's picture.

So it's supposed to be hard to get the gun into battery? on my 32 WS I have to grip the lever with both hands to get it into battery.

swheeler
11-18-2019, 04:18 PM
Correct, the case in the pic is not crimped. It's just a dummy round with old brass being used to check the bullet fit.

I made up another one with bullet seated deeper and crimped on the front driving band using the Lee Factory Crimp. It looks good and seems strong enough. I'll make a few rounds and watch closely for any signs of the bullets getting seated deeper under recoil.

251263

That looks better than the rifling engraving as much as you started with, I think I would seat out enough to just show engraving on very front of the drive band also and test both ways for accuracy. You have to have a combination of both accuracy and function, nothing worse than de bulleting in the field.

Larry Gibson
11-18-2019, 06:13 PM
So it's supposed to be hard to get the gun into battery? on my 32 WS I have to grip the lever with both hands to get it into battery.

Guess your definition of "firmly" is a bit different than mine. On both my M94 Winchester 30-30s finger pressure while gripping the stock is sufficient, easily done and all the "firmness" needed. when operating the action fast for a follow up shot the cartridge is slammed home with normally cycling of the lever/breach bolt.

Green Frog
11-19-2019, 11:36 AM
CamoWhamo, if you post that picture and question over on the ASSRA (American Single Shot Rifle Association) forum, you will be likely to receive encouragement to shoot it like that. The hot shoe shooters in the single shot game frequently seat their bullets all the way into the lands and grooves, up to .125” or even more ahead of the case mouth. If that round will feed without problems and you don’t see excess pressure signs (with normal posted loading data you shouldn’t) you should get gilt edge accuracy out of it, and if the loaded round can be ejected without pulling out, you’ve hit the jackpot! :mrgreen:

Froggie

charlie b
11-21-2019, 03:22 PM
Yes, shoot it. Best accuracy is normally when the bullet is engaged as others have posted. When shooting targets it is a normal practice and it is my preferred method.

BUT, if it is a hunting gun that you may have to unload in the field then I would seat them deeper to make sure the bullet comes out of the rifle when cycling the action.