Reading bullet bases

[gunlaker]

If I had some HDPE I'd definitely try some, but LDPE is almost all that I ever use. I don't even remember seeing an accuracy difference with veg vs. LDPE ( except with paper patch where I notice a definite improvement with LDPE ). I think I started using LDPE after talking with Dan. I'm happy with them, even though they are pretty non-traditional.

I have some recovered bullets that show small fins where the grooves meet the base, but I don't worry about it a lot.

Chris.

[DAVE ROELLE]

LDPE Compressive strength. 1400 psi

HDPE Compressive strength 4600 psi

Normal BPC operating pressures 14000 to 25000 psi

Perhaps ldpe on lighter loads and hdpe on heavier loads

Worth thinking about

[Aviator]

Soooo, I'm new to reading bullet bases.

Is the deformation on this bullet base enough to worry about (for long range target rifle)?

This is a 540 gr bullet fired at about 1320 fps from a 45-70.

DSCN0840_smaller.jpg

[Kurt]

I ordered sheets of .03" and .06" LDPE from MSC and I must have pushed the wrong button and got the HDPE instead. It is a lot harder but cuts well in the press mounted wad punch but it causes a problem with my tight PP chamber cases bulging the cases out seating the wads. That bulge is enough that the round will not chamber.This is not a problem with standard chambers because of the wider case necks.
Even running the case back through sizing die the wad pushes the neck out again. The LDPE in the tight case neck will create a dome and the case wall will stay unchanged.
I ended up giving the sheets to my Wife to use for cutting boards

IMG_3211.jpeg

[Geologist]

Years ago, I had a lot of problems with case stretching and separations using LDPE wads, especially with those ludicrously thin-walled Starline cases. Dan T. recommended I try HDPE and I have never had a problem since.

[BFD]

Soooo, I'm new to reading bullet bases.

Is the deformation on this bullet base enough to worry about (for long range target rifle)?

This is a 540 gr bullet fired at about 1320 fps from a 45-70.


DSCN0840_smaller.jpg

No, the deformation on the base is fine. But the deformation on the sides of that bullet might be a huge issue. Big ugly crevasses like that? Bad news.

What you are looking for on the sides are just shallow grooves running approximately lengthwise. Not deep gullies running across...

[Shadow 4]

Soooo, I'm new to reading bullet bases.

Is the deformation on this bullet base enough to worry about (for long range target rifle)?

This is a 540 gr bullet fired at about 1320 fps from a 45-70.


DSCN0840_smaller.jpg

No, the deformation on the base is fine. But the deformation on the sides of that bullet might be a huge issue. Big ugly crevasses like that? Bad news.

What you are looking for on the sides are just shallow grooves running approximately lengthwise. Not deep gullies running across...

C'mon Brent, those are like fletchs on an arrow, helps with the perfect spiral don't cha know

[BFD]

There is fletching and there is fletching. 5" cut wing turkey feather vs. flu-flus. Grease grooves being the latter.

[Aviator]

Soooo, I'm new to reading bullet bases.

Is the deformation on this bullet base enough to worry about (for long range target rifle)?

This is a 540 gr bullet fired at about 1320 fps from a 45-70.


DSCN0840_smaller.jpg

No, the deformation on the base is fine. But the deformation on the sides of that bullet might be a huge issue. Big ugly crevasses like that? Bad news.

What you are looking for on the sides are just shallow grooves running approximately lengthwise. Not deep gullies running across...

You mean like this one?

IMG_20200129_142715458_smaller.jpg

When I was at the Harris, MN long range match last summer, a nice fellow by the name of Kurt was trying to enable me into trying paper patch, and this is one of the handful of bullets that he gave me.
I do have to say that the bump-up looks to be very nice, just coming forward to the indicator mark that he put on the bullet. And there is almost no deformation of the base.

By the way, I caught these bullets in a homemade box that I made a couple weeks ago.

IMG_20200105_153204199_smaller.jpg

It is 8 feet long, and filled with pillow stuffing.
My first attempt, the bullet went thru the full length, and out the end....
Before the second attempt, I doubled the amount of stuffing, packing it in as tight as I could.
The next four attempts, the bullets stopped about 6 to 7 feet in. They end up cocooned inside a tight twisted ball of stuffing. I think they do sustain some abrasion as they are drug to a stop, but the bullets seem fairly intact.

[Kurt]

You must have stopped at the my pillow pillow factory in Minnesota to get your soft supply
Nice box. I'm surprised that the bullet survived so well. That is a lot handier than snow
What did that bullet's length end up? I can compare the before and after unless you have that measurement. I like your box.

[BFD]

I recall lots of guys at Harris that were trying to help enable you.... Yes that is much better. Nice box. Much like mine, but better filling obviously. Oiled sawdust has lots of negatives.

[Aviator]

We'll, I figured you would ask!
Unfortunately, the bullet slipped out of my fat fingers as I was unraveling the fiber fill, and it has a flattened point......
So, it measures 1.406 long, compared to about 1.457 for an unfired bullet, but the flat tip ruins the comparison.
The distance from the base of the bullet to the patch indicator is about .030 inch shorter on the fired bullet, and that length change is definitely NOT in the nose. I do not think the nose length changed much at all, but I can't prove it (since I was clumsy).

Yes, I think the people at JoAnn Fabric store were confused by some old fart buying 40 lbs of fiber-fill!!!! Two giant boxes!
I used about 25 lbs so far.

By the way, I don't think I would want to open the top of the box outside on a windy day....

[Aviator]

I recall lots of guys at Harris that were trying to help enable you....

True!

But Kurt is the only one that gave me sample bullets!

I am going to shoot the remaining ones at a target soon.

[BFD]

Don't leave the end of the box open either. The mice will love you a little too much if you to.

If you are worried about sparks igniting in that stuff, like I do in the sawdust, I stapled a plastic trash bag over the end (my end is completely open) and shoot through it. I figure most of the sparks won't make it inside. I'm sort of a worry wart about fires.

How far did the bullet travel in the stuff?

[Aviator]

Based on a sample of four, they all ended up between 6 and 7 feet in.

I don't know if it is any better method of catching a bullet for examination than any other. Jury is still out.
It is a bit of a nuisance, but I decided to give it a try. Heck, I saw a reference to someone else doing it on "The Internet", so it must be a good idea, right?

Before trying this, I tried catching bullets in milk jugs. I have done that before, but I have never observed a very high success rate for bullets that have substantial penetration characteristics. The last time, I saved gallon milk jugs for quite awhile. I lined up and fired. The bullet obviously started tumbling about jug number 7, and came out the side of jug number 11. Set up again and tried another shot. It also came out the side of jug number 11.

Seems like we rarely get enough snow here to go that route, and it is sort of seasonal anyway. So I decided to try this method.

I think next time out I will shoot maybe 4 to 6 samples into it before taking it inside and opening it up to get the bullets.
For different variations, I can put center punch marks (or similar) on the bullet bases, so I can tell them apart.

One observation: In my (limited) sample of Qty 1 each, bullets from the same mold, the 12:1 alloy bumped up noticeably less far into the nose area than the 16:1 alloy. I probably will repeat this, with a few samples of each.