Thread: 223 Lapua brass

anyone running a 1 in 8 with 75eldm, lapua brass and 2208 fed 205 srp

looking to compare recipes. Have GRT and a couple of manuals to reference too.

cheers

Why?

Close. I'm running the 75 and 73gn ELDM's Nosler Brass Fed 205 Primer and 25gns of 2208. This is a compressed load which I worked up to. Velocity is 2795 out of a 20" barrel in my Tikka T3x. Velocity, POI and pressures are the same for both the 73 and 75gn.

context
@Pommy

75gr eldm - Seated long @2.440", adi brass, cci400, 2206h 24.5gr = 2920fps 22" tikka barrel.
Must be over pressure but is only slightly cratering the primer, no other signs or bolt/extraction issues.
I modified a tikka mag to take 2.6"+

Over all length is the critical thing with that bullet to avoiding pressure in a 223. You’ll get over pressure fast if you have to run close to SAMI length for mag feeding

That being said I run them loong COAL 2.45” with 24.6gr of 08 for 2900fps I’m the 24” tikka. I know a mate that runs them up to 25gr
From other loads I’ve seen around the 24.5gr mark is a sweet spot

Lapua brass is much heavier than most US brass so has less capacity. I would work up towards the listed velocity which is likely to be reached with less powder. Case capacity could be an issue as well.
GPM.

Originally Posted by grandpamac

Lapua brass is much heavier than most US brass so has less capacity. I would work up towards the listed velocity which is likely to be reached with less powder. Case capacity could be an issue as well.
GPM.

Overall weight is a poor measure of internal capacity. I cant find (be bothered looking) my old data but a quick check this morning on only a single case of each

.................................................. ................Lapua .........ADI.........Hornady...............OSA

Dry weight (grns) .........................................98.8..... .......99.7.........96.7...................94.2


Capacity in grains of water..............................30.4........... .30.2..........30.2..................30.9

Maybe a fair bit of variation too ? ADI and OSA come from same plant over here?

On topic , I run 25gns of 2208 behind a 80.5 Berger seated just off the lands in a t3 varmit. Single load or in a waters 2.8 magazine. LC brass, fed match primers.


Sent from my iPhone using Tapatalk

What is the 'context' you seek @ilikepie? Sanity check? Realistic velocity expectations? You don't mention if you are using a good chronograph to find out what speeds you are getting with your combination of components in your rifle.

If you give GRT good quality inputs then it will give you good guidance. I'm not sure if you're aware of it, but you can tune the powder profile to reflect what you have available more closely.
@grandpamac - in 223 the Lapua brass is similar in capacity to most other brands (in my experience). The one that might catch people out is the Starline brass as it is one of the lowest capacity brands on the market. It is great stuff particularly given the price, but caution is required (as always) when working up loads for it with data based on higher capacity.

Originally Posted by Dicko

Maybe a fair bit of variation too ? ADI and OSA come from same plant over here?

On topic , I run 25gns of 2208 behind a 80.5 Berger seated just off the lands in a t3 varmit. Single load or in a waters 2.8 magazine. LC brass, fed match primers.


Sent from my iPhone using Tapatalk

Yes even within brands you get variation but my point was not that a particular brand will have X capacity but that over all weight is often not representative of internal capacity when comparing brands. I used a much larger sample when i first tried it and thats the conculsion I reached, repeated this morning in a very small sample.

Greetings All,
Granted that changes in weight do not match changes in case capacity but it is indicative as shown by @sneeze figures. My own weighing showed (for the .223 only) Federal being the lightest at around 89 grains including fired primer up to the continental brass including Lapua at around 105 grains. Rather than try to measure case capacity (which should be to the base of a seated projectile) with water (messy and inexact) I just segregate the brass by head stamp and if possible lot and develop loads working up with the chronograph to the Hodgdon/ADI velocity adjusted for barrel length. It works for me. Recent work with BM8208 has shown significantly less velocity than the Hodgdon/ADI data suggests and more in line with the Hornady data so for me a decent chronograph is an essential piece of kit for load development.
Regards Grandpamac.

Originally Posted by grandpamac

Greetings All,
Granted that changes in weight do not match changes in case capacity but it is indicative as shown by @sneeze figures. My own weighing showed (for the .223 only) Federal being the lightest at around 89 grains including fired primer up to the continental brass including Lapua at around 105 grains. Rather than try to measure case capacity (which should be to the base of a seated projectile) with water (messy and inexact) I just segregate the brass by head stamp and if possible lot and develop loads working up with the chronograph to the Hodgdon/ADI velocity adjusted for barrel length. It works for me. Recent work with BM8208 has shown significantly less velocity than the Hodgdon/ADI data suggests and more in line with the Hornady data so for me a decent chronograph is an essential piece of kit for load development.
Regards Grandpamac.

My completely unscientific sample of one shows 2 cases very similar with one other supporting your claim and one that dosn't so Im struggling to see " indicitive" in a 50-50ish result. I guess one mans indicative is another's disproven theory. I don't think bullet seating depth is relevant when simply comparing capacities across brands.
Reading between the lines here it seems you've not actually checked internal volume? just gone off the old collective wisdom of more weight is less volume?

The only way to measure case capacity is full to the top of the neck with H20, otherwise its too inaccurate, even flush, convex, concave with the mouth makes a difference

Apparently Sth Island water weighs less that Nth Island water so bare that in mind with your calculations

Originally Posted by Kiwi Greg

Apparently Sth Island water weighs less that Nth Island water so bare that in mind with your calculations

I think its because of the abundance of energy drinks in the NI