estimate my speed

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Bryan Carvalho

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Hey everyone,
I've been on here for awhile and I hear guys talking of a program called quickload (i think). I guess guys use it to estimate speed or pressure of a given load. I was wondering if one of you guys could help me with this load as I don't have acess to a chrony at the moment. Im load developing for acustom 308, obermyer chamber, 24" 12 twist barrel. The load is 42.5gr of rl-15, 178gr hornady bthp, lapua case, cci br2 primer and seated right around the lands and groves. This new bullet from hornady looks awsome and has an impressive bc but im concerned that its going a little on the slow side but grouped around .3". Thanks for any help guys.
 
I would hazard that you are in the 2600-2700 range.

I'll have to look at my reloading records with RL-15 but I'd have to say you are somewhere in the above velocity range.

I've done lots of chronying with 168-180gr bullets out of my 24" bbld rem with both RL-15 and Varget and go from 2600 at the heavy end and up to 2700-2750 at the high end depending on powder loads.
 
I did some loads with 180gr SMKs in my .308 but can't recall the exact velocities. Wasn't a hot load either. IIRC they were in the high 2500 range like 2560 or so. I don't have my numbers here.

They were also with Lapua cases and BR2 primers. Either Varget or RL-15, can't recall the powder charge off the top of my head.. All in the notebook.

They grouped horribly though

I still think you might be in the low 2600s though or in that ballpark.
 
Bryan Carvalho said:
Hey everyone,
I've been on here for awhile and I hear guys talking of a program called quickload (i think). I guess guys use it to estimate speed or pressure of a given load. I was wondering if one of you guys could help me with this load as I don't have acess to a chrony at the moment. Im load developing for acustom 308, obermyer chamber, 24" 12 twist barrel. The load is 42.5gr of rl-15, 178gr hornady bthp, lapua case, cci br2 primer and seated right around the lands and groves. This new bullet from hornady looks awsome and has an impressive bc but im concerned that its going a little on the slow side but grouped around .3". Thanks for any help guys.
Click to expand...

What is your cartridge OAL? Need it for quickload, makes quite a difference how deep your bullet is seated.
 
QL estimates 2568 fps at 50,049 psi.

If your rifle is custom chambered to minimum dimension, then press would probably be a little higher (velocity too, but not as much) than QL estimated.

Remember that QL is an estimate, and there's lots of real world stuff that it doesn't consider - bullet jump and throat dimensions, and more. But it's usually pretty close, and in this case you have a fair margin of safety from maximum pressure.
 
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Bryan, ceriksson's guess based on experience with similar combinations is probably as good as anything else, short of actually firing it over a chrono.

It's quite promising that this load is shooting well for you at short range. If you are interested in seeing if it shoots well at longer range, then at some point you need to either fire it over a chrono or shoot it at long range. Do whichever one that first becomes possible (though there are advantages and disadvantages to each; do both if you can).

Don't worry about your bullet being "too slow". If it is a slick low-drag bullet (it is), if it shoots accurately for you (sure looks promising), then sooner or later you'll be able to fire it at full speed (i.e. as quickly as anybody else is able to get it to go) with good accuracy. If this particular load really is "too slow" (by which I mean, is slower than can reasonably and safely achieved in your rifle or any .308 rifle), that will sort it out during your load development and workup.
 
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