My friend loaded some 6.5-284 shells w/ berger 140gr hunting bullets and 4350. He shot a 5-shot spread and got a 100fps difference between the highest and lowest number. Is this normal? They were all within .001 COAL, and the charges were measured using the RCBS charge master. All new brass using the same primers. The shot string was shot about 1 minute between each shot.
Normal max FPS spread?
- Thread starter raider1v1
- Start date
M
milo 2.0
Guest
Re: Normal max FPS spread?
100 fps difference is too much for an effctive load.
When I shoot through a chrono, I shoot about as fast as I can, I'm looking at numbers, not accuracy.
You have too shoot through the chrono the same each time, not high once, then low, left and right also.
100 fps difference is too much for an effctive load.
When I shoot through a chrono, I shoot about as fast as I can, I'm looking at numbers, not accuracy.
You have too shoot through the chrono the same each time, not high once, then low, left and right also.
Re: Normal max FPS spread?
thats what i thought, he was aiming in the same spot each time. what could be the cause of this spread?
thats what i thought, he was aiming in the same spot each time. what could be the cause of this spread?
Re: Normal max FPS spread?
He just isn't in his accuracy node, he needs to do load development and not just pick an amount of powder.
Extreme spread in 5 shots shouldn't be over 30 , for a reasonable load.
He just isn't in his accuracy node, he needs to do load development and not just pick an amount of powder.
Extreme spread in 5 shots shouldn't be over 30 , for a reasonable load.
Re: Normal max FPS spread?
he did some load development at 47.0, 47.5, 48.0, 48.5, and 49.0
The 47.0 was the most accurate, but only by just a hair. he was wanting to use the 49 for extra speed.
Should the rule be to go with the most accurate always?
he did some load development at 47.0, 47.5, 48.0, 48.5, and 49.0
The 47.0 was the most accurate, but only by just a hair. he was wanting to use the 49 for extra speed.
Should the rule be to go with the most accurate always?
M
milo 2.0
Guest
Re: Normal max FPS spread?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Raider1v1</div><div class="ubbcode-body">
Should the rule be to go with the most accurate always? </div></div>
If the goal is to hit what you're aiming at yes. If you just want to make noise and scare shit, no.
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Raider1v1</div><div class="ubbcode-body">
Should the rule be to go with the most accurate always? </div></div>
If the goal is to hit what you're aiming at yes. If you just want to make noise and scare shit, no.
Re: Normal max FPS spread?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: milo-2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Raider1v1</div><div class="ubbcode-body">
Should the rule be to go with the most accurate always? </div></div>
If the goal is to hit what you're aiming at yes. If you just want to make noise and scare shit, no. </div></div>
sorry, ill be clearer. The smallest group was about 3/8", and this was about 1/8" larger. This was his hunting round, and the ranges are within 350yds. i know that at long ranges, the 1/8" will start to become an issue, as well as the FPS spread.
so do you suggest that he chronos the 47.0 gr load to see what the spread is?
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: milo-2</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Raider1v1</div><div class="ubbcode-body">
Should the rule be to go with the most accurate always? </div></div>
If the goal is to hit what you're aiming at yes. If you just want to make noise and scare shit, no. </div></div>
sorry, ill be clearer. The smallest group was about 3/8", and this was about 1/8" larger. This was his hunting round, and the ranges are within 350yds. i know that at long ranges, the 1/8" will start to become an issue, as well as the FPS spread.
so do you suggest that he chronos the 47.0 gr load to see what the spread is?
Re: Normal max FPS spread?
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">sorry, ill be clearer. The smallest group was about 3/8", and this was about 1/8" larger. This was his hunting round, and the ranges are within 350yds. i know that at long ranges, the 1/8" will start to become an issue, as well as the FPS spread.</div></div>
I could repeat that several times and come up with several different results. 1/8" is well within my margins. I typically get big ES's at lower pressures.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">sorry, ill be clearer. The smallest group was about 3/8", and this was about 1/8" larger. This was his hunting round, and the ranges are within 350yds. i know that at long ranges, the 1/8" will start to become an issue, as well as the FPS spread.</div></div>
I could repeat that several times and come up with several different results. 1/8" is well within my margins. I typically get big ES's at lower pressures.
Re: Normal max FPS spread?
when i chrono new loads i always try to run at least 10 through the chrono.
I will usually load 7 rounds of each wieght for my initial test
IE:
7-24
7-24.5
7-25
7-25.5
7-26
I then shoot 2 loads of each through the chrono up to the max charge looking for PSI signs and velocity readings.
When PSI signs are noticed. I note that, that charge recipe is my rifles MAX with those components.
What i will then do is shoot the first 3 (excluding any unsafe loads that may be loaded up) rounds at my target starting with one at 24,24.5,25,25.5,26 then back to 24 till ive expended all the rounds.
that should give me a good indication of accuracy through the different charge weights and they wont be skewed by barrel temps.
with the lowest charge
Then i go home with all my data and sort the information taking in PSI signs, velocity, es, sd, and accuracy to determine the NEXT round of development.
The hunting load i worked up for my 25-223 took almost 200rnds of experimentation and i still havent played with primers or seating depths. The recipe shoots very very well and is minute of groundhog at 400yds LOL
when i chrono new loads i always try to run at least 10 through the chrono.
I will usually load 7 rounds of each wieght for my initial test
IE:
7-24
7-24.5
7-25
7-25.5
7-26
I then shoot 2 loads of each through the chrono up to the max charge looking for PSI signs and velocity readings.
When PSI signs are noticed. I note that, that charge recipe is my rifles MAX with those components.
What i will then do is shoot the first 3 (excluding any unsafe loads that may be loaded up) rounds at my target starting with one at 24,24.5,25,25.5,26 then back to 24 till ive expended all the rounds.
that should give me a good indication of accuracy through the different charge weights and they wont be skewed by barrel temps.
with the lowest charge
Then i go home with all my data and sort the information taking in PSI signs, velocity, es, sd, and accuracy to determine the NEXT round of development.
The hunting load i worked up for my 25-223 took almost 200rnds of experimentation and i still havent played with primers or seating depths. The recipe shoots very very well and is minute of groundhog at 400yds LOL
Re: Normal max FPS spread?
as an update:
I called RCBS, they said it was due to Winchester primers and suggested federal.
I called hogdon and they said it was due to new brass, and it would even out after we used once fired brass.
I tried to call berger, but their phone system kept disconnecting me.
as an update:
I called RCBS, they said it was due to Winchester primers and suggested federal.
I called hogdon and they said it was due to new brass, and it would even out after we used once fired brass.
I tried to call berger, but their phone system kept disconnecting me.
Re: Normal max FPS spread?
You really don't need to call around. The companies are just giving you their 'thoughts' to get you off the phone. You already had alot of good advice here.
It doesn't sound like you did proper load development. Do an OCW test. The charge your at might be extremely finicky.
Accuracy is the final judge, but if the load proves accurate at 100 yards, thats all it means. An accurate 100 yard load with a huge velocity spread will most likely be inaccurate at distance. You want to find something that is accurate and has the least amount of SD (ES isn't as accurate of a judge)
You really don't need to call around. The companies are just giving you their 'thoughts' to get you off the phone. You already had alot of good advice here.
It doesn't sound like you did proper load development. Do an OCW test. The charge your at might be extremely finicky.
Accuracy is the final judge, but if the load proves accurate at 100 yards, thats all it means. An accurate 100 yard load with a huge velocity spread will most likely be inaccurate at distance. You want to find something that is accurate and has the least amount of SD (ES isn't as accurate of a judge)
