Lets talk overall legth....

[Zeus]

Since I'm so new to loading the 204 I have a few questions.....specifically about the 39 grain sierra Blitz bullets. Both the manuals I have list Case Overall Length of 2.250". Now I understand that these measurements are used to ensure that the particular load works in any rifle as far as length and pressure is concerned but in relation to the bullets it seems awful short. The bullet is almost seated past the beginning of the ogive. Does anyone here load this particular bullet longer? If so, how much longer should I try?

I'm going to test a few different COL's and I'd like some idea on how much room these things have to grow. I guess I need to find out how far the distance to the lands is with each particular bullet.

[Rick in Oregon]

Zeus: As you probably know, when the 204R was being considered for commercial use, it was decided (unfortunately) to shorten the OAL of the loaded cartridge to ensure function through the AR magazine/platform. This move results in the silly deep seated factory bullet you describe in order to fit the AR magazine. All bolt guns can usually benifit being seated closer to the lands, but not always.

Unless you need the repeater function of your rifle, seat those 39's out as long as you want. In my Sako M75 Varmint that loves that bullet, I've only got something like .150" of bullet in the case, as it loves to be closer to the lands compared to the bodacious .120" worth of jump the factory setting would give. It shoots bugholes seated out, but can only be fed as a single shot as a result. No problem for me, as most of my shooting is from the bench at colony rodents where we always load single shot anyway.

Some guns don't mind this jump, but all five of my .20 cal rifles much prefer being closer to the lands. I only shoot my Kimber 84M Varmint as a repeater, and it shoots the 32's fine with rounds that fit the mag, but it's the only bird in the safe that will. Most of my rifles shooting the 39gr SBK are all almost a full .100" over factory OAL.

[Zeus]

Thanks for the quick reply Rick! The 39 grainers are getting shot out of an TC Encore Pro hunter so fitting a magazine wont be a problem. I'm going to try to load a few today and see what happens....Without knowing the dimensions of my rifles chamber, how much of an increase should I try? I was thinking something along the lines of .025" at a time or something in that neighborhood.

[Rick in Oregon]

I usually start out with .010" increments, then .005" for final tweaking of the COAL. And by that, I'm talking comparator overall length. I'm using the old Stoney Point tool, now offered by Hornady.

Another thing to consider when seating out, is that by doing so, you've gained internal volume, so theoretically you've reduced pressure with the same charge. My Sako 39 SBK load is over max using 10X, gets a whopping 3,980 fps from the 39gr, but shows zilch pressure readings, even mic'ing the case web.

There's alot to be learned and gained by playing with seating depth; one of the primary gains I've found is stellar accuracy once you get away from the SAAMI 204R overall loaded length restrictions imposed by the AR and magazine box restrictions.

[Zeus]

I figured this would lead down the gadget road. I'm going to try to do the best with what I have and we'll see how it turns out.

[Rick in Oregon]

I figured this would lead down the gadget road.

Oh baby, are you ever right about that!

Precision handloading is about one of the most gadget-oriented activities known to man!

[bigt73]

I usually start out with .010" increments, then .005" for final tweaking of the COAL. And by that, I'm talking comparator overall length. I'm using the old Stoney Point tool, now offered by Hornady.

Another thing to consider when seating out, is that by doing so, you've gained internal volume, so theoretically you've reduced pressure with the same charge. My Sako 39 SBK load is over max using 10X, gets a whopping 3,980 fps from the 39gr, but shows zilch pressure readings, even mic'ing the case web.

There's alot to be learned and gained by playing with seating depth; one of the primary gains I've found is stellar accuracy once you get away from the SAAMI 204R overall loaded length restrictions imposed by the AR and magazine box restrictions.

how do you get those speeds?
i just ran QL and it said i would need 26grs of re10x which is 100% case fill and 70800psi in a 26inch barrel and thats with 32 h20 capacity..

[Zeus]

Well, I loaded up some test loads and it seems that the rifle likes a little jump. I loaded up 3 sets with the same powder charge.... and 3 different COL's 2.280, 2.300 and 2.320. The best group was with the shortest one @ about an inch. But as much as I hate to admit it I don't think my beloved Varget is going to work with the rifle/bullet combo. It looks like I'll be investing in some 10x or 4895...Darn it! I was getting good velocity at 3750 fps, I hope to maintain velocity in that range and it looks like these other powders might do that for me.

I also ran some factory Hornady ammo over the chrono....Holy smokes that stuff is cruising along at 4300 fps out of that 28" barrel!

[Joe O]

Thanks for the quick reply Rick! The 39 grainers are getting shot out of an TC Encore Pro hunter so fitting a magazine wont be a problem. I'm going to try to load a few today and see what happens....Without knowing the dimensions of my rifles chamber, how much of an increase should I try? I was thinking something along the lines of .025" at a time or something in that neighborhood.

If thats the case,slit the neck of a dummy round,seat the bullet 2.400 AND INSET INTO THE BARREL REMOVED FROM THE ACTION.iF IT TOUCHES THE LANDS REMOVE AND MEASURE.NOW YOU CAN SUBTRACT FROM THERE FOR WHAT YOU WANT OFF THE LANDS.SOME CHAMBERS ,YOU MIGHT NOT TOUCH AT 2.400.PLAY WITH THAT,OR $$$

[Bodei]

Well, I loaded up some test loads and it seems that the rifle likes a little jump. I loaded up 3 sets with the same powder charge.... and 3 different COL's 2.280, 2.300 and 2.320. The best group was with the shortest one @ about an inch. But as much as I hate to admit it I don't think my beloved Varget is going to work with the rifle/bullet combo. It looks like I'll be investing in some 10x or 4895...Darn it! I was getting good velocity at 3750 fps, I hope to maintain velocity in that range and it looks like these other powders might do that for me.

I also ran some factory Hornady ammo over the chrono....Holy smokes that stuff is cruising along at 4300 fps out of that 28" barrel!

I think I am going to try some IMR 8208 XBR as I've seen good velocity reports with the .204 and its supposed to be very temperature insensitive. Looks like "mini-varget." I hope it works in my 55+ grain .223 bullets as well as Varget

[Tokimini]

After a lot of experimentation (9 different COLs from 2.250 to 2.326) I discovered my rifle likes 2.306 inches. Five shot groups at 100 yds went from just under half an inch to sub quarter inch groups with the right COL.