Please help the new guy.

[JOHNNIE WALKER]

I am very new to reloading. Just started with my 260rem. I did a lot of research and noticed that 4350 was a good powder to use so thats what I wanted to start with. With supplies being very hard to find, I was able to find some A4350. With a practice I was quickly able to cut the size of my groups in half. The problem I'm having is the differences in speed each round has. They very any where from 1-70 fps. I was very precise with my powder. I weighed each charge with a digital scale to make sure they were exact, and used a trickler to adjust. I evan double checked a few times to make sure. Is this problem caused by the type of powder I'm using or am I missing something?

 

[RT2506]

Could be a number of things. Primers would be my first thing to change along with proper case prep. One thing that has helped me is removing the burr inside the case of the primer flash hole. If you are using Lupua cases they don't have a burr because the holes are drilled not punched. AA4350 is a good powder. I have used it for years and found that in most cases it is within what different lots of IMR 4350 would be as to load data.

 

[varmintH8R]

I am very new to reloading. Just started with my 260rem. I did a lot of research and noticed that 4350 was a good powder to use so thats what I wanted to start with. With supplies being very hard to find, I was able to find some A4350. With a practice I was quickly able to cut the size of my groups in half. The problem I'm having is the differences in speed each round has. They very any where from 1-70 fps. I was very precise with my powder. I weighed each charge with a digital scale to make sure they were exact, and used a trickler to adjust. I evan double checked a few times to make sure. Is this problem caused by the type of powder I'm using or am I missing something?

I would guess that your powder charge accuracy is not the driver of your velocity inconsistency. There are a bunch of things guys do to reduce velocity extreme spread (ES). Changing primers or powders, making sure neck tension is as consistent as possible, finding a "sweet spot" for powder charge, playing with seating depth, etc.

Before you go about changing a million variables, I think it would be good to look into some areas that may lead you to believe you have an ES issue where none exists:

What Chrony are you using?

Is your 70fps variance in the same day of shooting?

Are your loads at outdoor temp when you start and stop shooting (not from a warm car or pocket)?

What is your routine (cooling between shots, cleaning, etc)?

What are your groups, and at what range?

Is the ES that you are observing effecting your drops at the range you hope to shoot?

Sorry for the 20 questions, but the more we understand about how you are getting these results, the more likely you are to get advice that can get you to an easy solution.

Brandon

 

[Mark611]

consistency starts with your cases! you need to weigh them and sort them before and after you prep them, different case weights will have different internal volume and will perform different from shot to shot if not separated, this is another cause of velocity extremes, if you want to get you ES down you need to do all the needed work to fully prep your cases, this includes turning the necks, along with the other info you have been givin

 

[JOHNNIE WALKER]

This what I'm using-
Rem Brass
41.8 gr A4350
140gr SST
CCI BR-2 primers
This loads produces very consistent groups well inside of .5 @100 yds. I have shot a few groups that were 1 ragged hole, no joke.
I'm using Hornady dies and a hornady press. I played with this load several times before taking it to a friends to use his chrony. I'm not sure what brand it was. I shot fifteen rounds through it, and was very concerned about the differences in speed. It was around 15 degrees out. Everything was sitting out and at the same temp. I wasn't shooting fast and there was no pattern to the differences. With this load being so accurate I really didn't think it would have this big of a difference in speed between shots. Thats kind of why I was concerned. Am I missing something?

 

[varmintH8R]

This what I'm using-
Rem Brass
41.8 gr A4350
140gr SST
CCI BR-2 primers
This loads produces very consistent groups well inside of .5 @100 yds. I have shot a few groups that were 1 ragged hole, no joke.
I'm using Hornady dies and a hornady press. I played with this load several times before taking it to a friends to use his chrony. I'm not sure what brand it was. I shot fifteen rounds through it, and was very concerned about the differences in speed. It was around 15 degrees out. Everything was sitting out and at the same temp. I wasn't shooting fast and there was no pattern to the differences. With this load being so accurate I really didn't think it would have this big of a difference in speed between shots. Thats kind of why I was concerned. Am I missing something?

Some chronographs are prone to error depending on lighting, conditions, or just their overall capability. If it were me, I would take that combo that shoots one hole at 100 and stretch it out to the longest range you intend to shoot it at. If it still holds 1MOA or less, don't fix what ain't broke. If it opens up dramatically at longer ranges (vertically more than horizontally) it will be time to start tweaking.

My 2C

Brandon

 

[MNbogboy]

+1 on the above posts...

By his results it sounds like the OP is starting out right and doing a good job....

My first thought also..."the chrony"....Light & weather conditions with even the good ones can cause fits...also distance to chronograph...12'-15' should be a minimum....

As mentioned above the longer range test above is the best thing to do in my opinion before changing anything...

Randy

 

[Sargesniper]

Johnny, two words come to mind with your issue. "NECK TENSION". I had the same problem. I "bit the bullet" and bought Lapua cases and never looked back. If you seat your bullet and feel more resistance on some than others then that may be the answer to your question. It may not solve your problem completely but you will have far better cases in the end. What dies are you using? FL or Neck Only? What brand bullet and primer combo has an effect also. Welcome to reloading,sometimes it is like a dog chasing his tail. Only change one thing at a time though as you may complicate matters more. Good luck with it. Keep everyone up to date on your progress.
............. SEMPER FI ............ SARGESNIPER

 

[JOHNNIE WALKER]

I really appreciate all the advice. My little girl, who just loves to help daddy, managed to get a hold of my turrets on my scope and gave me about a 30'' adjustment before I could get to her. She was proud of herself. Such a good helper. I didnt have them set to zero, so we resized a bunch of brass and are planning to do some shooting this weekend.

Would a crimp die help control the speed of the bullet?

 

[Sargesniper]

I really appreciate all the advice. My little girl, who just loves to help daddy, managed to get a hold of my turrets on my scope and gave me about a 30'' adjustment before I could get to her. She was proud of herself. Such a good helper. I didnt have them set to zero, so we resized a bunch of brass and are planning to do some shooting this weekend.

Would a crimp die help control the speed of the bullet?

Crimping will hurt you on accuracy if you are shooting a bolt gun. I dont use the expander ball on my dies either. I use enough neck tension so as the projectile cannot be pulled out of the case with my fingers. They just glide into the case without much resistance.
Have fun and don't let it drive you up the wall.
SEMPER FI ............. SARGESNIPER