My New 284 Build and Chrono results

Below is a pictures of my new 284. I am still developing a load for it. I only shot these rounds @ 100yds to get the chrono results.

Below are pictures of the Chrono printouts. I don't know if my Chrono is broke, but the results change with every load.

Has anyone experienced the same results that my 55.5 load is showing? Going from 54.5 to 55.5 grns pushed the bullet over 200fps faster, 4831SC. ? ? ? Hard to believe .2 grains makes this much difference on the SD & ES.

180 grn Berger Hybrids, 4831SC, CCI LR primers, Lapua brass, .050 off the lands

Savage PTA action, SSS evolution trigger T&T'd by SSS, Heavy McGowen 28" 9twist barrel, SSS Heavy BR stock

Just need your opinions.

The 284 rifle:
http://i957.photobucket.com/albums/a...7/DSC02528.jpg

54.5 load, 3 rounds, brass and primers looked good
http://i957.photobucket.com/albums/a...s4437/54-5.jpg

55.5 load, only 4 rounds, brass and primers looked good, no pressure signs
http://i957.photobucket.com/albums/a...s4437/55-5.jpg

55.7 load, 5 rounds, blew one primer, others showed slight pressure signs, to hot
http://i957.photobucket.com/albums/a...s4437/55-7.jpg

What bullet and how are they grouping? The 55.5 load looks extremely consistent.

180 grn Berger Hybrids, @ 100yds all 4 rounds were a tight cloverleaf.

Below is the picture of my targets at 100 yds, I wasn't even trying as I was more interested in the chrono results.

Next rounds will be shot at 300yds.

http://i957.photobucket.com/albums/a...7/DSC02538.jpg

Well the group definitely reflects the consistency! Great group. I don't think I would change a thing.

Your numbers look great and your targets much better. I dont see a problem anywhere...

Something doesn't seem right with that big of a jump in velocity. My 28" CBI netted me 2860 with 56gr of 4831sc with the hybrids. If your getting almost 3000fps, then you got a super fast barrel and shouldn't change a thing.

It is one whole grain of power. I don't see how a 200 fps is so incredible.

Quote:

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Originally Posted by Nandy

It is one whole grain of power. I don't see how a 200 fps is so incredible.

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All guns are different, but if I remember right mine was roughly 30fps difference from 55 all the way to 56.2. So over 200fps is a big deal. At least to me it would be...

My .260 Ackley jumped 200 fps between a grain and a half. It happens, lots of variables come into play like brass type and thickness chamber tolerances and the barrel just may be fast. His numbers look in line with what they show over on accurate shooter.

If it were a shehane, you would be correct. Not many people getting over 2950 with a straight 284 unless the barrel is 32"+... just saying...

Just to be on the safe side, I am going to load up some starting at 54.8 and up to 55.4. Also, on the 54.8 & 55.1 I will try setting the bullets only .015 off the lands, plus leave a set .050 to see the actual difference. The 55.5 loads showing a 0.00 SD is still unbelievable. I know it's only 4 rounds, but I am going to try them again and report the numbers. Some are telling me they wish they could get these speeds out of their Shehane's.

While the chrony may not be correct with actual FPS (should be close though) it does show the consistency of the load. ES and SD is incredible!

If possible use another chrony to varify the load data and it'll give you a better idea if it's the actual FPS.

BTW.........VERY NICE RIG!!!

Im assuming your best target group and your best number group is the same(55.5). If so I would not worry about the other charges and built around that. Go up and down .1 or .2 grains and then play with the bullet seating. Do not change more than one thing at the time. If you are shooting in the same location keep an eye on the temperature and wind. Also, do not leave a shell in the chamber or even the magazine when you are waiting for the barrel to cool. You will get crazy results that way, dont ask me how I know... Definitely shoot at more than 100 yds. That group is too tight at a 100 to tell much about improvement. Of course, you might know or planed on all of this already in which case just ignore me...

Nandy, I look at every post. I was only shooting at 100 yds to break the barrel in and see the chrono results. I am going to try a few other loads starting at 54.8, then I will move to 300 yds, then 600yds. And yes, this gun is sensitive to "any" changes, .1 grain of powder or any seating change. That's why I am going to try a few more with a lower charge.

My normal procedure is to chamber a bullet when my target appears, every time, weather practice or a match. IMO it's the only safe way to shoot and also the only way to have consistancy with your groups. An ole timer told me several years ago never let a load sit in the chamber too long as it heats up the round. It made since and I have been following his advice ever since.

That rig looks to be real problematic.I'll cash you out on it so you can move on to another project.,,,please

Quote:

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That rig looks to be real problematic.I'll cash you out on it so you can move on to another project.,,,please

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OK, might be time for another project, LOL

UPDATE: I loaded up more rounds this weekend and headed to the range with my chrono. Sunday the results were completly different! See the below picture. 55.3grns showed promising results. One thing I can say is the ES and SD are very low and consistant in this rifle. It looks like the first of the year I will get a new chrono and go from there. I am trying to get 2,925fps, but it looks like I will have a charge of 56.2+ to acheive this. 55.9grns were showing pressure signs, so I don't know if this is going to be possible. The first test were done with Federal brass. The below results I was using 6.5x284 Lapua necked up brass.

I don't know if RL17 is the answer, but let me know if it's worth a try. I would think it would show pressure signs as well. Let me know your thoughts, Dennis

http://i957.photobucket.com/albums/a...7/DSC00080.jpg

I would try it. I've had good luck with RL17 in most of the rifles I've tried it in.

One thing about it.....you'll know AFTER you try it. :p

According to everything I am reading, I should start out at 53.0 grns of RL17 and work up.

Any comments on the starting load of RL17?

Rl-17 will definitely get you where you want in terms of velocity, only question is whether it will give you the accuracy you want as well.

53.0 seems a bit stout to me.

175 grn bullet max load in a 280 Remington is 50.5 according to what I have been able to find, and the 280 has more capacity than the 284.

Please verify that load before you try it.

Post how it goes.......been thinking of a 284 myself.

I ran 52.5gr of reloader17 in mine. Velocity was roughly 100fps faster and accuracy was there, but I couldn't get the temp stability issues out of my head so I stuck with 4831sc.

Another 284 shooter here so I'm curious: what is your bbl length? Cartridge Overall Length?

I agree with Apache that you should give RL-17 a try and also that you should start lower than 53 gr. w 180s. Rl-17 will get you to the same velocity with lower pressures or give you a bit more room to push the max if you're so inclined. I built a 284 with a 9 twist 24" Pac Nor pre fit on a Savage 10PC. This isn't a dedicated target gun, so I stuck with factory components otherwise so am limited to mag length (3") for COAL. Using RL-17 with 160 AccuBonds I started seeing mild pressure signs (no flattened, cratered or blown primers, just light ejector marks on the case head) at 51.5gr which gave me 2890fps. This was during warm weather, which is what I expected during season so I backed it off to 50.8 gr for 2830fps. I could probably run the 51.5 this time of year w RL-17. I have some load tests made up right now starting at 47 grains RL-17 and going up to 49 with 168 VLDs. I would expect to be able to go several grains higher as the bearing surface difference between the 160 accubond and the 168 VLD is pretty dramatic (the accubond having much more) but the wind has kept me from testing. I may max out on case capacity before I reach pressure max with the VLDs(as you might w your 180s depending on your setup).

I've really enjoyed my 284. I used to shoot a 308win and wanted to move to something that had a bit better ballistics and that would function in my rifle with only a barrel swap. In my opinion, if you want to push a 180 7mm bullet over 2900 a 7wsm or 280AI might be more practical if you're not set on a 284. Obviously a 284 can do it as Dennis has demonstrated, but you've gotta have it set up just right. (I'm guessing that Dennis has at least a 28" barrel? or is loading to around 3.2" COAL?)

I think it's funny that the 284 isn't more popular. It has better ballistics than a 7mm-08 or 308 and will function in a rifle with exactly the same components and I've found that the recoil is just as tame as a 308.

Anyways, sorry for the rambling :) Good luck with your load development! Things are looking great so far!