Sierra .223 load data?

[JDGray]

Loading for my R700 LTR, I've noticed data for 52-53gr bullets, using H335 is quite a bit higher with Sierras data, compared to Lee's Second edition, and Speer #12. I am loading Sierra 52gr Match Kings, so I feel the Data should be good, but Sierras max is 27.6gr compared to Lee's 26.0gr, and Speer's 26.5gr max loads. They all start near 24gr. Sierra has specific bolt action, and AR15 data, where the others don't specify, I figure this is the reason for the higher max. Other powders seem to match the other manuals numbers however, what gives with the H335? Any one with other manuals care to look up this bullet, powder combo, I'd welcome the info

 

[MEHavey]

If I assume a 31cc case volume (my own meas of Winchester & Lapua) w/ an OAL of 2.26", QL says a 52gr SMK over H335 yields:

26.0 - 45,600 psi
26.5 - 48,500 psi
27.0 - 51,500 psi

...which seems reasonable even at max.

~~~~~~~~~~~~~~~~~~~~~~~~

IF (on the other hand) the effective case volume is 1cc less (30cc - some other web sources), however, you are running ~4,000 psi more for all loads
At 27.0gr H335 you will have exceeded SAAMI max by 500psi, and will be squishing your primer pockets open after repeated firings.

 

[Ky Larry]

If Sierra published the data, you can trust it.(Unless it's a typo.)

 

[rcmodel]

Lee has no test facilities. All their data is simply a reprint of others manufactures data available elsewhere.

Hodgdon lists 26.0 grains of H335 with the 53 grain Sierra HP as Max, giving 3,300 FPS at 52,000 CUP.

That out of a 24" 1:12 twist barrel.

I see no need to go beyond that, as MAX or over-max pressure & velocity seldom proves to be the most accurate load anyway.

rc

 

[JDGray]

Dupe

 

[JDGray]

Thanks for the responses

Hodgdon lists 26.0 grains of H335 with the 53 grain Sierra HP as Max, giving 3,300 FPS at 52,000 CUP.

That out of a 24" 1:12 twist barrel.

I see no need to go beyond that, as MAX or over-max pressure & velocity seldom proves to be the most accurate load anyway.

Sierras accuracy load is 26.9gr H335, and is why I asked the question, and thats not a max load, as 27.6 is according to their data. I usually stop short of max loads in my work ups, but went up to 26.9 this time. I'm hoping accuracy is good before that set of 5 cartridges is fired.
http://accurateshooter.net/Downloads/sierra223rembolt.pdf

After reading the intro of my link, loads were tested in a 1-14" twist, hows a 1-9" gonna effect that data?

 

[Doug b]

Lyman #49 manual for sierra bullet no.1410 shows a start load with H335 of 24.5gr. and a max.of 27.2gr. 34,200 psi and 51,500 psi respectivly. Test specs are Universal Receiver 24" with 1-12" twist and Colt AR15 20" with 1-7" twist. Data goes up to an 80gr.bullet,this is probably were the 1in7 twist was used.Rem. cases and Rem 7 1/2 primers,and 2.25" oal.Hope this helps.

 

[rcmodel]

hows a 1-9" gonna effect that data?

I believe pressure will be higher in a 1:9 then in a 1:14.
You are bound to have higher start pressure in the faster twist barrel.

How much difference I could not even guess.
And I can't prove it either!

rc

 

[JDGray]

Well....I shot my test loads and found something intresting. The first 5 rounds on a clean, cold bore, were the most accurate. Groups opened up every .5gr step up in powder, untill I got to 26.9gr, which is Sierras accuracy load, and the group went right back to almost size of the first. Velocity was very close to Sierras data, per increase. Not a bad load, but a reloader is always looking for better. The bottom, right group was a load that worked in my AR15, not so good in the remmy.

 

[Clark]

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The High Road, nor the staff of THR assume any liability for any damage or injury resulting from use of this information.

Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24"
barrel, 3203 fps, 49,300 CUP

Test 8-19-2003: Ruger #1, CCI 400 small rifle primers, LC brass once fired
processed from Scharch and prepped by me, 55 gr Vmax moly, H335

pic left to right: unfired 27 gr, 28, 29, 30, and 31 gr.

unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload 69 kpsi QL estimate
29 gr, extractor groove .329", 15% overload 80kpsi QL estimate
30 gr, extractor groove .3295", 19% overload 92kpsi QL estimate
31 gr, extractor groove .3320", 23% overload 106kpsi QL estimate

The case heads fail at 86,000 psi.
I have fired the same 223 cases over and over at 66,000 psi with long brass life.
The brass will grow so fast with FL sizing that trimming is needed every firing or two. So I neck size.

What does it all mean?
The .223 Remington has been registered with SAAMI at 55,000 psi average max pressure.
The published loads are based on that.
Splitting hairs over 223 published does not then make much sense to me.

 

[JDGray]

Thankfully my primers didn't look like those

Intresting data, thanks for the post.

 

[Clark]

Do we keep having this conversation, or is this The Truman Show?
http://www.thehighroad.org/showthread.php?t=490281

 

[Walkalong]

Shooting one at 25.5, one at 26.0, one at 26.5, and one at 26.9 proves nothing.

I could give an explanation for all of those errant shots, especially if that "called" flier is just that. (Might be wrong, but that's not the point.....)

Shoot an Agg with each load and study it carefully. Pay close attention to conditions when you shoot them.

But....let's assume you missed no conditions and made no shooting errors......the first group was at a sweet spot, it opened up, and then another sweet spot was at 26.9...but only if that pattern is repeatable, over, and over.

Sorry, it drives me nuts when decisions are made on one group. I am tired and cranky......... I need to go to bed....... AC

 

[JDGray]

Do we keep having this conversation, or is this The Truman Show?

I certainly don't remember what I posted in Dec!! Sorry to annoy ya
Different rifle, same 8lb jug of H335 to burn up. Next time I look up W231 data for my 45,380,32, I'll probably post about the wide variance in my manuals, so get used to it, or don't reply!

 

[JDGray]

Thanks to those with usefull replies, this broken record is good!

Mods please close.