Fast Barrel

[Henryrifle]

This is long but I really would like to learn something.

Executive summary:

I have a barrel that shoots a lot faster than I would expect. The problem is the ES is bad and won't work for long range F-Open, the rifle's intended purpose. It shoots better when freshly cleaned but the more rounds that go through it the worse the SDs get. Intuitively, that makes sense to me. Does that mirror other's experience? Additional questions at bottom of post.

TLDR section:

I have a 32" 7mm barrel chambered in 284 Winchester and I am shooting 180 Hybrids over H4350 and H4831sc. I do know what the chamber is supposed to be and it is in the range of normal for the cartridge--.3175 neck diameter and .225 free bore. Loaded Lapua expanded and neck turned 6.5X284 rounds show .310 neck so, plenty of room there. There is a donut problem but loading well above the donut and and have cut them out a few times.

Understanding that barrels are individuals and the internet is maybe equal parts noise and information, this barrel is shooting a lot faster than I'd expect.

50.2 Grains of H4350 shoots in the high 2830s to low 2840s. You have to go down to 48 grains of H4350 to get into the mid 2750s.

53.6 grains of H4831sc yields 2840 FPS and if you ant to shoot in the 2740s you have to drop to 49.8 range of charges.

Above measured with Labradar and initial trigger.

The problem with this is that the SDs are erratic. Some groups are shoot within 5 FPS while others are 60 FPS. This usually indicates that you are not on a node, but if that is true, I can't find the node.

I shot the gun in a 600 yard mid range event with my best load and dropped two points to vertical. The gun shoots in the .2s at 100 but you could never trust it at 1000 with SDs like that.

I've switched primers and powder. H4350 is definitely better than H4831sc but still has similar issues.

Unfortunately, I don't know the specification of the Bartlien barrel on this rifle but it almost has to be tight to achieve those velocities.

Will be changing barrels shortly as I want to stop wasting components and time but would like to learn something.

Questions:

What could cause a barrel to shoot significantly faster than you expect?
If you have a barrel that shoots faster, is it common to see higher than normal ES and SD numbers?
What might it mean that the barrel shoots better groups and lower ES when clean?

Thank y'all,
Henryrifle

 

[22BRGUY]

I think I'd just try a bit of longer range stuff to actually see those results. Reason I'm saying that is I have a good friend that has a chrony also and his was reading 100 to 150 fps faster speeds than mine with the same loads. Also his seemed more eratic than mine in it's readings.
Just a thought.
Best Wishes

 

[B Nettesheim]

Those loads seem normal to me
I would investigate your ignition

 

[jr600yd]

Your loads seem pretty normal to me. I know the SD-ES numbers can drive you nuts. What does the target tell you? Dropped two to vertical? We’re they both in the same place, maybe one high one low? Maybe it was you! Try a bullet seating test at range

 

[Henryrifle]

One high, one low and lower X count than one would expect at that distance.

200-14
199-11
199-8

@B Nettesheim: I am not super sure how to check the ignition. I did load the action into the lathe and using .001 gauge measured the distance the firing pin traveled from cocked to relaxed and got about what I expected, 245 thou. There is .015 bolt play when the spring is relaxed so maybe it is really 230 thou. Either way that seems to be within the acceptable range. Spring has less than 1000 shots on it but maybe worth replacing. All primer strikes look perfect--no one would characterize them as light.

I appreciate these answers and don't want to seem defensive about what I have done. I don't know the answer(s).

It could be that the barrel doesn't like the 185s Hybrids. That would be an insurmountable problem.

 

[gme]

have you checked for heavy copper fouling at the muzzle?

 

[Henryrifle]

Always hate to discuss barrel cleaning as that can be very a very polarizing topic. I use a Hawkeye borescope and normally clean with BoreTech products - Jag and brush. In addition to regular cleanings usually 100 rounds or so (a normal single-day match) I do use Iosso when I think the barrel needs it. I am not going for a bare metal cleaning as that often really changes the MV but close to it. As I have lathe I am not too worried about the edges of the crown. Usually takes less than an hour to recrown.

 

[Coyotefurharvester]

Have you confirmed the velocities with drop at distance? Your powder charge to velocity is/seems high. If you are going to rebarrel yourself, lop off a half inch first and check velocity/sd again(old school BR tune), take another 1/2 if you see numbers begin to "normalize".

 

[Sandstorm]

Here is what I have found and from talking to friends that shoot F-open.
284 Win nodes are 2760-2780 and 2820-2850...these work from fellow 284 shooters.
I shoot a Shehane but its only a little faster and really the same as a straight 284.
I shoot at 2870-2880 range..and my Lapua 284 brass is loaded with 4831sc
See if you can find the right speed and then test at 100 ( if it works) if it shoots small
then go shoot 1000 and see how it does.

 

[David Christian]

This is long but I really would like to learn something.

Executive summary:

I have a barrel that shoots a lot faster than I would expect. The problem is the ES is bad and won't work for long range F-Open, the rifle's intended purpose. It shoots better when freshly cleaned but the more rounds that go through it the worse the SDs get. Intuitively, that makes sense to me. Does that mirror other's experience? Additional questions at bottom of post.

TLDR section:

I have a 32" 7mm barrel chambered in 284 Winchester and I am shooting 180 Hybrids over H4350 and H4831sc. I do know what the chamber is supposed to be and it is in the range of normal for the cartridge--.3175 neck diameter and .225 free bore. Loaded Lapua expanded and neck turned 6.5X284 rounds show .310 neck so, plenty of room there. There is a donut problem but loading well above the donut and and have cut them out a few times.

Understanding that barrels are individuals and the internet is maybe equal parts noise and information, this barrel is shooting a lot faster than I'd expect.

50.2 Grains of H4350 shoots in the high 2830s to low 2840s. You have to go down to 48 grains of H4350 to get into the mid 2750s.

53.6 grains of H4831sc yields 2840 FPS and if you ant to shoot in the 2740s you have to drop to 49.8 range of charges.

Above measured with Labradar and initial trigger.

The problem with this is that the SDs are erratic. Some groups are shoot within 5 FPS while others are 60 FPS. This usually indicates that you are not on a node, but if that is true, I can't find the node.

I shot the gun in a 600 yard mid range event with my best load and dropped two points to vertical. The gun shoots in the .2s at 100 but you could never trust it at 1000 with SDs like that.

I've switched primers and powder. H4350 is definitely better than H4831sc but still has similar issues.

Unfortunately, I don't know the specification of the Bartlien barrel on this rifle but it almost has to be tight to achieve those velocities.

Will be changing barrels shortly as I want to stop wasting components and time but would like to learn something.

Questions:

What could cause a barrel to shoot significantly faster than you expect?
If you have a barrel that shoots faster, is it common to see higher than normal ES and SD numbers?
What might it mean that the barrel shoots better groups and lower ES when clean?

Thank y'all,
Henryrifle

Have you shot any other barrels on this action? Do you have another barrel chambered the same to rule out the action/bolt/bolt spring/ignition?

If you strip the bolt do you see any wear marks on the firing pin or drag lines where the pin protrudes from the bolt face?

How is the bedding? Are the action screws tight?

Have you checked that specific lot of powder against others?

Have you checked different boxes of brass?

Aside from the above, some barrels just shoot faster due to something in the manufacturing process.

Have you run your powder ladder down to the 2710 to 2730 range to see if a node presents itself? A guy in our summer league had just such a barrel and placed 10th at SWN this past Feb shooting this low node in a fast barrel. ‍

 

[v63800]

This is long but I really would like to learn something.

Executive summary:

I have a barrel that shoots a lot faster than I would expect. The problem is the ES is bad and won't work for long range F-Open, the rifle's intended purpose. It shoots better when freshly cleaned but the more rounds that go through it the worse the SDs get. Intuitively, that makes sense to me. Does that mirror other's experience? Additional questions at bottom of post.

TLDR section:

I have a 32" 7mm barrel chambered in 284 Winchester and I am shooting 180 Hybrids over H4350 and H4831sc. I do know what the chamber is supposed to be and it is in the range of normal for the cartridge--.3175 neck diameter and .225 free bore. Loaded Lapua expanded and neck turned 6.5X284 rounds show .310 neck so, plenty of room there. There is a donut problem but loading well above the donut and and have cut them out a few times.

Understanding that barrels are individuals and the internet is maybe equal parts noise and information, this barrel is shooting a lot faster than I'd expect.

50.2 Grains of H4350 shoots in the high 2830s to low 2840s. You have to go down to 48 grains of H4350 to get into the mid 2750s.

53.6 grains of H4831sc yields 2840 FPS and if you ant to shoot in the 2740s you have to drop to 49.8 range of charges.

Above measured with Labradar and initial trigger.

The problem with this is that the SDs are erratic. Some groups are shoot within 5 FPS while others are 60 FPS. This usually indicates that you are not on a node, but if that is true, I can't find the node.

I shot the gun in a 600 yard mid range event with my best load and dropped two points to vertical. The gun shoots in the .2s at 100 but you could never trust it at 1000 with SDs like that.

I've switched primers and powder. H4350 is definitely better than H4831sc but still has similar issues.

Unfortunately, I don't know the specification of the Bartlien barrel on this rifle but it almost has to be tight to achieve those velocities.

Will be changing barrels shortly as I want to stop wasting components and time but would like to learn something.

Questions:

What could cause a barrel to shoot significantly faster than you expect?
If you have a barrel that shoots faster, is it common to see higher than normal ES and SD numbers?
What might it mean that the barrel shoots better groups and lower ES when clean?

Thank y'all,
Henryrifle

Henryrifle
what primers are you using

 

[Henryrifle]

I want to answer some of your questions because they are good ones.

Other Barrels - I did try a 6 Dasher barrel on this action/rifle and it shot okay. No problems with ES but it didn't shoot very well--high .3s over 250 shots. I believe that is more an issue with the reamer I spec'd. I should stick to reloading and shooting and use proven reamers.

Firing pin - The action is a Borden and the firing pin seems fine. There is still a lot for me to learn about actions but I don't see anything out of the ordinary--keeping in mind I have an inexperienced eye for this.

Bedding - this was recently redone, prior to the 600 yard match. Originally the bedding had some issues. it wasn't great but is now. The new bedding has made an improvement in accuracy at short range but no change to ES.

Powder - Have not checked against other lots, but both H4350 and H4831sc are very fast. Could be that I have fast lots of both.

Different brass - No, and this is a good consideration. Have been using the same 100 pieces of brass. I've been reluctant to use new brass because this is not really the chamber I want to end up with. I'd prefer a no-turn chamber to minimize donut formation. That doesn't mean that I wouldn't turn it a little but want a little larger neck like .319 or .320.

Speed ladder - I have not been below 2745 and this is a good point. I wanted to be at 2750 or higher and closer to 2800 but I should test a little lower to see what there is to see. 2710 FPS will be approximately 47.3 grains of H4350 and 50.9 grains of H4831sc.

Primers - I've used CCI BR2s, CCI 200s and Federal 210m. No statistical difference between those 3. have settled on CCI 200s.

Henryrifle

 

[22BRGUY]

Another Possible Suggestion:
I shoot a 260AI. About 3 months ago I went on this site and asked the question
of what powder to use in that cartridge as I had tried at least 4 and was having a difficult
time finding a consistent node.
A member of this site that shoots competition and is a consistent winner suggested
Reloader 23 as absolutely the most stable, least temp sensitive to use. I was loading
+- 47 1/2 to 48 grains of the same powders you mentioned. Less with 4350 but thought
of it when you mentioned your loads.
To be honest I haven't tried it yet myself but surely want to at first chance I get.
I know that even over the course of the same day, temps and conditions can change.
He said that Re23 just doesn't care. It is always the same and he impressed me
as one who would know. Just a thought.
Best Wishes

 

[Acyr]

Have you taken the shroud off the bolt and checked the retaining pin for clearance inside the shroud body?
Make sure it's not rubbing against the inside of the shroud.

 

[Sandstorm]

a little larger neck like .319

Just have your gunsmith open up your neck to .320. I have done this on mine, I still
turn my brass just a little to clean it up .013 and I feel better about my neck tension, They seem to shoot real good too. As for the donut ..I dont worry about it and seat mine well above that anyway.

 

[v63800]

This is long but I really would like to learn something.

Executive summary:

I have a barrel that shoots a lot faster than I would expect. The problem is the ES is bad and won't work for long range F-Open, the rifle's intended purpose. It shoots better when freshly cleaned but the more rounds that go through it the worse the SDs get. Intuitively, that makes sense to me. Does that mirror other's experience? Additional questions at bottom of post.

TLDR section:

I have a 32" 7mm barrel chambered in 284 Winchester and I am shooting 180 Hybrids over H4350 and H4831sc. I do know what the chamber is supposed to be and it is in the range of normal for the cartridge--.3175 neck diameter and .225 free bore. Loaded Lapua expanded and neck turned 6.5X284 rounds show .310 neck so, plenty of room there. There is a donut problem but loading well above the donut and and have cut them out a few times.

Understanding that barrels are individuals and the internet is maybe equal parts noise and information, this barrel is shooting a lot faster than I'd expect.

50.2 Grains of H4350 shoots in the high 2830s to low 2840s. You have to go down to 48 grains of H4350 to get into the mid 2750s.

53.6 grains of H4831sc yields 2840 FPS and if you ant to shoot in the 2740s you have to drop to 49.8 range of charges.

Above measured with Labradar and initial trigger.

The problem with this is that the SDs are erratic. Some groups are shoot within 5 FPS while others are 60 FPS. This usually indicates that you are not on a node, but if that is true, I can't find the node.

I shot the gun in a 600 yard mid range event with my best load and dropped two points to vertical. The gun shoots in the .2s at 100 but you could never trust it at 1000 with SDs like that.

I've switched primers and powder. H4350 is definitely better than H4831sc but still has similar issues.

Unfortunately, I don't know the specification of the Bartlien barrel on this rifle but it almost has to be tight to achieve those velocities.

Will be changing barrels shortly as I want to stop wasting components and time but would like to learn something.

Questions:

What could cause a barrel to shoot significantly faster than you expect?
If you have a barrel that shoots faster, is it common to see higher than normal ES and SD numbers?
What might it mean that the barrel shoots better groups and lower ES when clean?

Thank y'all,
Henryrifle

henryrifle
in my experience with 284 and 4350 50.2 grains would seem like a normal load for the fps you've stated on a barrel that has been run in.
If this a new barrel, as I've seen erratic speed up on new barrels up to 400 rounds on some brands.
.2's @ 100 is good result in load development if its repeatable in any rifle regardless of sd's so I doubt its barrel related. Br2's fed 210m primers will be best here
maybe check that you really are above the donut as I've seen differences in boat tails, bto's on 180 hybrids.
Nodes around 2770 2790-2800 2800-2830 is where I'd be looking.
You don't mention jump or jam maybe some bullets are pushing into the donut and the rifling when you load.

phil

 

[rebel107]

Jam the hybrids 15thou and try this with BR2's

 

[Walt Schmidlin]

When was the last time you changed the firing pin spring? I also agree with Acyr’s suggestion, prefer to start with relatively inexpensive attempts to rectify issues. Eliminates a variable.