CFE 300 BLK first thoughts update 1/28/17

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dellet
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by dellet »

Honestly I’d blame the powder first, you probably would have needed to be of at least .15 of a grain to get 25fps.

I’d probably load some 10.4 @ 2.160” expecting it to tighten up the spread around 1020-30.
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johnhefley
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by johnhefley »

I suppose it COULD be the powder, Dellet.

However, if you watched me reload, you'd probably shake your head. In the end, my goal is to load up LOTS of consistent, accurate bullets so I can go out and have some fun!

I'm pretty happy with the results so far - that is, these rounds are consistently subsonic, cycle perfectly, and are providing surprisingly consistent results on target.

I could keep fiddling with the load (and I might). But I'm a shooter first, and foremost. Reloading is a necessary evil for someone who spends as much time behind the trigger as I do.

jh
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dellet
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by dellet »

Using that bullet, the vertical spread at 100 yards will will be about 3/4" or more with a 30 fps ES. At 200 yards it will be closer to 5".

That powder can do better.

Drop a little powder to reduce velocity and start compressing until the primer pops out the bottom then, back off ten thou in your seating depth. :mrgreen:

When I got to .120" compression I started getting low teens and the occasional single digit ES numbers. It's worth giving it a try.
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johnhefley
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by johnhefley »

Now that sounds like fun, Dellet!!!

That was very, very specific. Thanks.

I would never have considered EVER compressing the powder until the primer starts to dislodge. Interesting.

For information, I'm using Carolina Brass cartridges cut down to 300 BLK from Lake City 5.56 range brass. So primer seating is snug.

I suppose "something will have to give" if I compress the powder enough. And theoretically, the primer might be the path of least resistance.

Armed with that information, do you still think I ought to try it?

jh
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dellet
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Re: CFE 300 BLK first thoughts update 1/28/17

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johnhefley wrote:Now that sounds like fun, Dellet!!!

That was very, very specific. Thanks.

I would never have considered EVER compressing the powder until the primer starts to dislodge. Interesting.

For information, I'm using Carolina Brass cartridges cut down to 300 BLK from Lake City 5.56 range brass. So primer seating is snug.

I suppose "something will have to give" if I compress the powder enough. And theoretically, the primer might be the path of least resistance.

Armed with that information, do you still think I ought to try it?

jh
You will deform the bullet before the primer falls out, so I guess, don't go that far. It was a bit of a joke.

Fired case with the primer still in. you want to be able to slip the bullet freely in the neck. Drop .10 grain off the last charge to drop velocity, you will get it back with the lower seating depth.

Drop the charge in the case, very lightly insert the bullet until it touches the powder, measure and record that.

Either turn the cartridge upside down to get the powder around the boat tail or twist the bullet down into the powder. Your not trying to compress the powder, just work it up around the bullet so you have 100% fill. Measure and record that.

I try to run that powder at 110% + case fill density.

So depending on the length of the tail, my COL might be as much as .150" shorter than the first number.
But I start at the second number and seat the bullet .010" deeper than the 100% fill measurement as a start.

If you do that with your current load you will be able to tell if you were compressed or not. I would throw a guess out and say probably not as much as you might think, if at all.

Work the ram slow so you're not compressing air in the case and then let the rounds sit over night an remeasure. If there is too much compression the rounds will grow over time due to the powder expanding and pushing the bullet back out.

I won't say you can't get into pressure problems with that powder, but I will say I tried to blow a primer with it and failed. Please don't take that as a challenge
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johnhefley
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by johnhefley »

Well, thanks for that, Dellet!

I had visions of going around without eyebrows for a long time with the "recommendation." :mrgreen:

For funsies, I suppose I could also try your method, but instead of using a fired case with a primer, I could shoot a bit of hot glue in the primer pocket, and force the bullet down until the hot glue dislodges. Just a thought...

This would avoid the whole matter of trapped air, etc.

jh
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dellet
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by dellet »

johnhefley wrote:Well, thanks for that, Dellet!

I had visions of going around without eyebrows for a long time with the "recommendation." :mrgreen:

For funsies, I suppose I could also try your method, but instead of using a fired case with a primer, I could shoot a bit of hot glue in the primer pocket, and force the bullet down until the hot glue dislodges. Just a thought...

This would avoid the whole matter of trapped air, etc.

jh
The primer won't move unless the pocket is loose, it was a joke. And to be clear I'm talking about the fired primer, not a live one.

To get an idea of what I'm talking about for displacing the powder with a slower stroke of the press, take your index finger and try to poke it into a bucket of sand as hard and fast as you can. Then if it's not broken take, the same finger and push it into the same bucket slow and easy. One way will work out better than the other.
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johnhefley
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by johnhefley »

OK, Dellet, you've got me thinking! So I spent a few minutes in my Evil Lair trying it out.

First off, a review of the measurements of my most recent load: 10.5 grains of CFE BLK:

2.181" COAL
1.46" Base to Ogive

Trickling in 10.4 grains into an empty, unfired case (spent primer, of course! :mrgreen: ), here's what I've come up with:

Bullet touching the powder, inserting the bullet by hand:
2.23" COAL
1.514" Base to Ogive

Bullet shoved hard into the powder by hand:
2.211" COAL
1.496" Base to Ogive

Bullet shoved in, and twisted by hand (with the cartridge upside down) in order to get the powder well above the boat tail:
2.177" COAL
1.463" Base to Ogive

It appears to me that my most recent load with 2.181" COAL/1.46" Base to Ogive is not only touching the powder, it probably has it under a bit of compression.

Do you see something different here?

jh

P.S. I fired another 20 rounds of the 2.181"/1.46" yesterday, and the cases and primers show no signs whatsoever of overpressure.
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dellet
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by dellet »

Subject: CFE 300 BLK first thoughts update 1/28/17
johnhefley wrote:OK, Dellet, you've got me thinking! So I spent a few minutes in my Evil Lair trying it out.

First off, a review of the measurements of my most recent load: 10.5 grains of CFE BLK:

2.181" COAL
1.46" Base to Ogive

Trickling in 10.4 grains into an empty, unfired case (spent primer, of course! :mrgreen: ), here's what I've come up with:

Bullet touching the powder, inserting the bullet by hand:
2.23" COAL
1.514" Base to Ogive

Bullet shoved hard into the powder by hand:
2.211" COAL
1.496" Base to Ogive

Bullet shoved in, and twisted by hand (with the cartridge upside down) in order to get the powder well above the boat tail:
2.177" COAL
1.463" Base to Ogive

It appears to me that my most recent load with 2.181" COAL/1.46" Base to Ogive is not only touching the powder, it probably has it under a bit of compression.

Do you see something different here?
jh

I would say 100% density, maybe barely compressed at 10.4 grns @ 2.180", depends on how hard you can compress it by hand.

So at the same 2.180" with 10.5 you had around 103-5%, really just starting to compress. I started getting really good numbers at 110%.

You could just shorten your existing load .010", but I think your velocity would stabilize higher, maybe 1050+. That was the reason for the suggestion for dropping .10 grain and then shorten .020", keep the velocity down closer to 1020-30.

One thing I have found to be a reasonable rule of thumb, is I can keep my velocity the same if I add or subtract .10 grain of powder and move the bullet the same .010". Add powder add length. Subtract powder subtract length.

So by looking at all your numbers, I think if you drop the charge to lose a bit of velocity, and compress the powder a bit more to tighten the spread than it was, you might just find a really sweet spot hopefully around 1030 or so.

My next step with your numbers would be 10.4 @ 2.166, 2.162, 2.158, 2.156. What makes that easy is a set of Redding competition shell holders. instead of adjusting the die, the shell holders are graduated .002".

Maybe works for you maybe not. But so far with that particular powder, if I can't compress it, I don't use it.

As far as pressure, I'm not sure there is a way to find a pressure problem with that powder in thst cartridge
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johnhefley
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Re: CFE 300 BLK first thoughts update 1/28/17

Post by johnhefley »

Again, Dellet, wow! Thanks.

I'll have to give it a try. I'm using standard Redding dies, so it'll be a little bit more work, but not much.

I just did a quick read on Nosler's website about calculating case fill density. So I have a VAGUE idea what it is.

Did you measure and arrive at your own powder bulk density and case capacity for your calculation?

I've searched high and low for CFE BLK powder bulk density, and can't find it anywhere.

jh
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