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Topic: Alpha LRP brass first time, save me from group convergence (Read 266 times) previous topic - next topic

Alpha LRP brass first time, save me from group convergence

I finally broke into the Alpha brass stash and decided to run a quick OCW ladder. I'd posted up before as to water capacity versus Starline, the consensus was start at 40.5 gr H4350 with 140 Hornady 140 gr BTHP and work up. I was accustomed to running 41.7 gr H4350 with the same bullet in Starline brass.

Browning X-bolt rifle, 28"pipe.

First, I was surprised at the level of effort needed to stroke the Alpha brass through a standard Lee collet die on a Forstner CoAx. True, I'm using a very shorty handle but still, compared to Starline the level of effort was remarkable. Measuring things, I was actually expanding the neck OD 0.001 by neck sizing.

OK, back on track. I ran the OCW today at 100 yards, it was about 35F ambient temperature with little to no wind. The first group ended up being 5 shots instead of 3 because I'd made an extra couple rounds and figured doing that at the starting charge made sense. The target was shot after a few warm up rounds.

I've pretty much figured this rifle likes to see 2800 fps or thereabouts as a node, and I still think that may be true with the Alpha brass.

But, what do I do about the first group? Best I ever shot. I know, OCW is not about groups but for me, that is sic. Should I play around a bit more in the 2730-2750 range? I'm never going to shoot past 300 anyway.

Thanks team!



 



Chris

Re: Alpha LRP brass first time, save me from group convergence

Reply #1
chris I wonder what 40.3 would look like as far as speed.... theirs 6 fps difference between 40 .5 and 40 .7... I would also load 5 at 41.4 and see what they do... im betting it would do well...
Grant

Re: Alpha LRP brass first time, save me from group convergence

Reply #2
40.5 is obviously more accurate than 41.5 but that doesn't mean you can't tune 41.5 if you'd rather run it there and shoot .2s & .3s instead of .0s & .1s 😊

The slower node seems wider, like Grant said it would be nice to see what 40.3 looks like.
Dave

Re: Alpha LRP brass first time, save me from group convergence

Reply #3
We can give you our opinion, but what do you want to do?
If you don't shoot past 300, I'd use the lower node.
It will save on barrel life, costs of using less powder
and such and brass life.( very little) If you shot it with new brass,
I would reload with the same brass (once fired) and
try to copy the results.
Say you shoot out to 300 yds. The first group is still sub. .5 @300yds. (damn)
The other is pushing .8   That first group, if duplicated, will give you a
cushion for wind or other things. The only reason you need speed, is for
shooting longer distances.  You know you have a shooter when most of
the groups are less than .5
Nice shooting.   8)  

Re: Alpha LRP brass first time, save me from group convergence

Reply #4
"I've pretty much figured this rifle likes to see 2800 fps..."

Good call!
See you at the range.

Re: Alpha LRP brass first time, save me from group convergence

Reply #5
Thanks for the replies team.

I agree with Ranger 188 that shooting with fire-formed brass will help to flush the truth.

I'm going to explore the lower node some more by starting lower and working up, it's a good excuse for a trip to the range if nothing else :)

BTW, no pressure signs whatsoever, even under magnification.
Chris

Re: Alpha LRP brass first time, save me from group convergence

Reply #6
Great shooting there Bike!!

There are several reasons to explore that 2700 + node. As Gregg said more economical, you don’t need the higher speed for distance, and three that lower node tends to be less sensitive- at least in my hands I usually see lees ES with the 2700 node versus the 2800 one.

Re: Alpha LRP brass first time, save me from group convergence

Reply #7
Nice shooting Chris, I think you are going to be very happy when you are finished!!!!! I would also work that lower node. Like others have posted, less wear and tear on barrel and brass for only shooting out to 300.

Re: Alpha LRP brass first time, save me from group convergence

Reply #8
While it might be the next benchrest world record load in waiting... it also may just be a fluke.  3 shots isn't enough to be statistically significant without a bunch more groups to show its repeatable (at all).

If it was me I would head back to the range with -both- some loads around 40.5 and 41.5

3 groups of 5 at 40.3, 40.5, 40.7 will tell you if it will hold up or not.

Re: Alpha LRP brass first time, save me from group convergence

Reply #9
While it might be the next benchrest world record load in waiting... it also may just be a fluke.  3 shots isn't enough to be statistically significant without a bunch more groups to show its repeatable (at all).
3 groups of 5 at 40.3, 40.5, 40.7 will tell you if it will hold up or not.

True dnellans, but that first group was 5 shots, not 3. Still, even 5 shots does not a trend make, trust me, there's no one better at fooling me than me :)

Totally agree with your suggestion, that's my plan.
Chris

Re: Alpha LRP brass first time, save me from group convergence

Reply #10
True dnellans, but that first group was 5 shots, not 3. Still, even 5 shots does not a trend make, trust me, there's no one better at fooling me than me :)

Totally agree with your suggestion, that's my plan.

5 makes it more believable and who isn't proud of their best group ever!  I think low .2's is my best single 5 shot group, I'd have to double check.

However... there is someone better at fooling you than you, its me fooling me!

If it holds up even close to that group you'll be in business for sure

Re: Alpha LRP brass first time, save me from group convergence

Reply #11
Excellent shooting.

Seeing your X-Bolt shoot like that makes me realize that when my X-Bolt Pro shot several 1/2 MOA 3 shot groups with Hornady 140 gr. ELD-M factory ammo was not a day of flukes but it was due to an excellent, factory lapped barrel and good ammo. Now I need to try 5 shot groups with my hand loads. Love those X-Bolts!

Eric B.
"I can stop buying guns and gun stuff anytime I want - I've done it hundreds of times."


Re: Alpha LRP brass first time, save me from group convergence

Reply #13
CaptGrumpy Sir,

Permission to speak freely, Sir.

If the Captain were to requisition a slightly larger pencil he may have a better chance of hitting the target.  Just my observation, Sir.

https://www.etsy.com/listing/572871954/44-inch-giant-pencil-large-pencil-big?gpla=1&gao=1&&utm_source=google&utm_medium=cpc&utm_campaign=shopping_us_c-art_and_collectibles-other&utm_custom1=e91619ab-0d0a-4dd0-baa4-d01dac4a64b5&utm_content=go_304499675_22746188555_78727425395_aud-318222619806:pla-116591723129_c__572871954&gclid=CjwKCAiA99vhBRBnEiwAwpk-uAtxTmGxfqO0qN7LjNAYEHSKkwebnwCEXRmGp-Qb_ova2idi7nBoGhoCibUQAvD_BwE
See you at the range.

Re: Alpha LRP brass first time, save me from group convergence

Reply #14
CaptGrumpy Sir,

Permission to speak freely, Sir.

If the Captain were to requisition a slightly larger pencil he may have a better chance of hitting the target.  Just my observation, Sir.

https://www.etsy.com/listing/572871954/44-inch-giant-pencil-large-pencil-big?gpla=1&gao=1&&utm_source=google&utm_medium=cpc&utm_campaign=shopping_us_c-art_and_collectibles-other&utm_custom1=e91619ab-0d0a-4dd0-baa4-d01dac4a64b5&utm_content=go_304499675_22746188555_78727425395_aud-318222619806:pla-116591723129_c__572871954&gclid=CjwKCAiA99vhBRBnEiwAwpk-uAtxTmGxfqO0qN7LjNAYEHSKkwebnwCEXRmGp-Qb_ova2idi7nBoGhoCibUQAvD_BwE

Permission DENIED! I hurt myself when I fell out of my chair and hit the floor while l was laughing!
I had a dream! Free at last, Free at last! Moving to Idaho