303 Brit Bullet Seat Depth

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I Dont Care About You

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Based upon how my thread on sizing 303 Brit and headspace has been going, this thread is sure to cause trouble. :popCorn:

I measured the distance to the lands on my No4 Mk2 for various bullets using a Hornady LnL tool. Then I measured the internal dimension of the magazine to determine the longest possible OAL for rounds. Then I measured up each bullet at the max OAL to fit in the magazine and came up with a distance to the lands for each bullet.

I have 150gr SP PPU, 175gr Hornady FMJBT and 180gr SP Spitzer bullets and all of them end up between 0.150" to 0.200" from the lands. For a modern target rifle I'd set bullets about .010" back from the lands.

Anyone know of a bullet that can be seated closer to the lands and still fit into the magazine OAL? Or is a gigantic jump to the lands just a fact of life in a LE?
 
Honestly I think that is just life. Load them like you want and single shot them or load them as long as you can do, while fitting the mag and feeds.
 
Re: gigantic jump to the lands just a fact of life in a LE?

It is if the barrel has throat erosion.

Nothing you can do about that, other than to try to find a NOS barrel [Good luck with that] except do what I do; seat your bullets no deeper than the case/neck junction & at least 1 calibre seating depth, in the .303's case, at least 0.314" [your neck length is 0.332"]

If you can find them, try some Speer 180 gr. RN, as the ogive is more rounded than Hornady.

You also want to stay away from BT bullets, especially in a barrel with throat erosion.

Don't forget that this is a 70+ year old rifle.

Finally, the closer to the lands, the higher the pressure, as the bullet can't get a running start.
 
Fact of life for sure.

Im loading 303B for an old win 1894, and found a crimp settled the groups some as well.

I have a 243 I'm also loading for and recently went to a 95 gr ballistic tip bullet. Could not get the thing to shoot until I went 0.0150 off lands. Previous 87 gr SP was fine near lands. Just the way it goes, so we load to the rifle.
 
jamesharrison said:
Re: gigantic jump to the lands just a fact of life in a LE?

It is if the barrel has throat erosion.

Nothing you can do about that, other than to try to find a NOS barrel [Good luck with that] except do what I do; seat your bullets no deeper than the case/neck junction & at least 1 calibre seating depth, in the .303's case, at least 0.314" [your neck length is 0.332"]

If you can find them, try some Speer 180 gr. RN, as the ogive is more rounded than Hornady.

You also want to stay away from BT bullets, especially in a barrel with throat erosion.

Don't forget that this is a 70+ year old rifle.

Finally, the closer to the lands, the higher the pressure, as the bullet can't get a running start.
Click to expand...

My rifle is an essentially unfired 1954 Mk2 so throat erosion is not a factor.

The 174gr Hornady have a long BT. Problem is the selection of bullets is kinda limited. I will prob get a hundred of the PPU 174gr bullets and try those. The PPU 150gr has a short BT but still ends up way off the lands.



wallz said:
Fact of life for sure.

Im loading 303B for an old win 1894, and found a crimp settled the groups some as well.
Click to expand...

A Lee factory crimp die is on the list of things to buy.
 
I didn't mention it because I only have about a hundred of them and no idea where I could get more but I have some 200gr cast RNHP with a gas check and those I can get within .050" of the lands no problem. They could prob go even closer without an issue but with this rifle I figure 50 thou is close enough.

Sadly these bullets are very hard Linotype and so they don't expand well, even with a huge hollow point. I've never seen another bullet like these ones. I bought them years ago packed into an old cigar box, at a gunshow.
 
The Mk VII cartridges used a flat base 174/175gr bullet. One of the biggest accuracy issues with the Lee Enfields is using a proper bullet. The boat tail bullets are not made for the LE, they are made for a Mosin, the LE likes a long bearing surface.

Try to get your hands on the 180gr Sierra bullet, yes it is a soft point but based on what most say this is the closest you can get to the flat base spire point. Also, do not discount the RN bullets, if you want to drop your bullet jump then move to a RN as the profile will grab the rifling earlier than using a long spire point.

I have to ask, what accuracy are you hoping to achieve? I notice that you are using mixed range brass, the first thing you need to do is fire form those brass in your rifle and then neck size them, this will give you the most consistent brass for sure. Then work up a load based on the magazine and cycling length and forget about the jump.

I see all these people talking about bullet jump and often they have not actually loaded or run rounds through their guns, just been talking theory. I have a 222 that is loaded to factory COAL but with 50gr bullets this thing will put 5 rounds in a group so tight at 100 yards that you can cover up all the cut paper with a dime, and I never worried about bullet jump.
 
Fox said:
The Mk VII cartridges used a flat base 174/175gr bullet. One of the biggest accuracy issues with the Lee Enfields is using a proper bullet. The boat tail bullets are not made for the LE, they are made for a Mosin, the LE likes a long bearing surface.

Try to get your hands on the 180gr Sierra bullet, yes it is a soft point but based on what most say this is the closest you can get to the flat base spire point. Also, do not discount the RN bullets, if you want to drop your bullet jump then move to a RN as the profile will grab the rifling earlier than using a long spire point.

I have to ask, what accuracy are you hoping to achieve? I notice that you are using mixed range brass, the first thing you need to do is fire form those brass in your rifle and then neck size them, this will give you the most consistent brass for sure. Then work up a load based on the magazine and cycling length and forget about the jump.

I see all these people talking about bullet jump and often they have not actually loaded or run rounds through their guns, just been talking theory. I have a 222 that is loaded to factory COAL but with 50gr bullets this thing will put 5 rounds in a group so tight at 100 yards that you can cover up all the cut paper with a dime, and I never worried about bullet jump.
Click to expand...

Thank you, this is the kind of info I was after. Seems like the 150gr PPU bullets I bought are the wrong bullet for the job. A bit of googling and it seems the Sierra 180gr bullet is not currently available in Canada. :(

I am midway through brass prep. Next step is to anneal and then size to fit my chamber. I'm fairly sure the headspace (to the rim) is fine in my rifle so I can fire form any short cases to the chamber without an O-ring. I think you are correct about loading to fit the mag and the bullet jump will be what it will be.

Not sure how much accuracy this rifle is capable of but we shall see. I've got very accurate target rifles so I'm happy to see how this No4 can perform.
 
I Dont Care About You said:
Thank you, this is the kind of info I was after. Seems like the 150gr PPU bullets I bought are the wrong bullet for the job. A bit of googling and it seems the Sierra 180gr bullet is not currently available in Canada. :(

I am midway through brass prep. Next step is to anneal and then size to fit my chamber. I'm fairly sure the headspace (to the rim) is fine in my rifle so I can fire form any short cases to the chamber without an O-ring. I think you are correct about loading to fit the mag and the bullet jump will be what it will be.

Not sure how much accuracy this rifle is capable of but we shall see. I've got very accurate target rifles so I'm happy to see how this No4 can perform.
Click to expand...

The bolt head on your No 4 rifle can be swapped if needed. Take a look at the bolt head, on the side you will see a number, they start and 0 and go up from there. If this is a barely fired rifle it probably has a 0 bolt head, which is great. If the action stretches, as it would in military use, you can swap the bolt head with a 1,2,3, etc, to get the proper headspace on the rim.

Since you have a newish No 4 rifle the chamber size will be less of concern for you.

I was lucky and got 200 180gr Sierra SP bullets when I started to load for my sporter NO YOU CANNOT HAVE THEM :).

Try the 150s, they may work for you. Another option for a plinking bullet is the 0.310 122-125gr bullets from the 7.62x39 cartridge, they shot just find in my No 4 rifles, not perfect but again it is a military rifle, these will not shoot to the sights.

Do you know if your rifle had 2 groove rifling or not? If it does then you may be able to swap the sizing ball in your dies to use a 0.308 bullet, you may get lucky and be able to use these more readily available bullets accurately.

There is nothing like playing to figure out what works, I think I enjoy that more than any other aspect or shooting.
 
I Dont Care About You said:
Based upon how my thread on sizing 303 Brit and headspace has been going, this thread is sure to cause trouble. :popCorn:

I measured the distance to the lands on my No4 Mk2 for various bullets using a Hornady LnL tool. Then I measured the internal dimension of the magazine to determine the longest possible OAL for rounds. Then I measured up each bullet at the max OAL to fit in the magazine and came up with a distance to the lands for each bullet.

I have 150gr SP PPU, 175gr Hornady FMJBT and 180gr SP Spitzer bullets and all of them end up between 0.150" to 0.200" from the lands. For a modern target rifle I'd set bullets about .010" back from the lands.

Anyone know of a bullet that can be seated closer to the lands and still fit into the magazine OAL? Or is a gigantic jump to the lands just a fact of life in a LE?
Click to expand...

Take a Hornady 174 round nose bullet and seat the bullet backwards, meaning the tip of the bullet is inside the case. Seat this bullet just enough to hold the bullet in the case neck. Now slowly seat the case into the chamber. The lands will seat the bullet and tell you where the rifling starts. You will find out where the rifling starts and come to the conclusion to seat the bullets to the crimping groove and forget where the rifling starts.

Both rifles below have long throats.

eNMuChI.jpg
 
bigedp51 said:
Take a Hornady 174 round nose bullet and seat the bullet backwards, meaning the tip of the bullet is inside the case. Seat this bullet just enough to hold the bullet in the case neck. Now slowly seat the case into the chamber. The lands will seat the bullet and tell you where the rifling starts. You will find out where the rifling starts and come to the conclusion to seat the bullets to the crimping groove and forget where the rifling starts.
Click to expand...

WHY would I do a job in a completely unreliable and half assed manner when I have a LnL gauge specifically deigned to measure the distance to the lands for each specific bullet?

I have already come to the understanding that magazine length is the start point for seating depth. The LnL gauge gives me the actual distance to the lands and knowledge is strength.
 
1.5 MOA would be excellent. I'd never shoot the thing past 300yds so even 2 MOA would do the trick every time. I've got accurate rifles and long range rifles. The LE is just for fun really.
 
Those 174 gr Hornady FMJBT wont do justice to the rifle, for several reasons. Sell them to Steelgray, so he wont have to shoot 308 pills.;) Get your hands on some 150 gr flat base Hornady pills, load them to min book load. This gives a MV close to design ~2450 fps. If your rifle is bedded properly, you should get close to optimal results. Oh - and your shoulder will appreciate "303 lite".
So when are you going to pick up a real 303 shootin iron like a Ross or a P-14? Throw a scope on them, work up a load, and they'll compete with any modern sporting rifle.
 
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Did a bit of research and it seems the following bullets would be the best choices for 303 LE. They are all flat based .311 or .312 size.

Hornady 150gr SP #3120
Hornady 174gr RN #3130

Sierra 150gr SP #2300
Sierra 180gr SP #2310

Speer 150gr SP #2217
Speer 180gr RN #2223

No to find a source for any of these ......
 
idk if has any relevance but the ruger 1 303s were made to old school spec per se an they have a long throat ? bullets like woodleighs 215 seated with half the neck can have bullets out closer but shape of projectile helps out-

us 303 ruger 1 guys cant find lands etc with most rounds.
 
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