6CM Accuracy Concerns - Am I expecting too much?

[J_Jacobson]

I have a Howa that has been rebarreled to 6CM with a 120fb using a 1:7.5" DD IBI Medium Hunter barrel by a very reputable gunsmith.
Whatever I do i cannot get a 10 shot group under 1.25MOA. Am I expecting too much?
I have swapped scopes, mounts, and chassis. Everything has always been degreased and paint penned.

Actions screws are tight on both the XRS and Bravo ive used.

Ive tried 107smk, 112MB, 108eldm, 80vt, and 87vmax. ADG Brass. Ar2209, ar2213sc, and AR2217. Fed GMM LRPs and Rem 9 1/2. Ive even fed it some factories.
All groups float between 1.2-1.5MOA groups for 8 to 10 shots. Sometimes i can see it wants to group, putting 5 or 6 of the shots into 0.3" then the rest of the group is scattered around it.

Am I being pedantic and this is good enough or have I forgotten something obvious?

 

[Deere_Man]

Is this a hunting rifle? If so, what does the first three shots look like when the barrel is cold?

1.5” for ten shots is just fine for a hunting rifle. She might settle down once you have a shot it some more.

How did you find this barrel manufacturer? I have never heard of them. I’m usually looking at Hart, Douglas, Krieger, Bartlein, Brux, Lilja, or Shilen.

 

[ResearchinStuff]

That's good enough to do the job, but not great. Try some h4350.

 

[Libtard McSocalist]

I’m going to have to reccomend some 109 and especially 105 hybrids. I start around .030 jump and go in/out from there. Powder wise I would look at h4350 and rl16. When in doubt yellow box and 4350 rarely disappoint in 6mms

 

[sierracharlie338]

Yep as stated h4350 is the way. Any of the Bergers or eldms should be printing respectable groups

 

[robtattoo]

A

Thread 'Your Groups Are Too Small'

Dec 15, 2022

Thought this was a great discussion about group sizes. Especially chasing a zero. Recommend anyone take a listen.

• ARK_Ginger
• Replies: 464
• Forum: Long Range Hunting

• 

 

[mtnbound]

I have a Howa that has been rebarreled to 6CM with a 120fb using a 1:7.5" DD IBI Medium Hunter barrel by a very reputable gunsmith.
Whatever I do i cannot get a 10 shot group under 1.25MOA. Am I expecting too much?
I have swapped scopes, mounts, and chassis. Everything has always been degreased and paint penned.

Actions screws are tight on both the XRS and Bravo ive used.

Ive tried 107smk, 112MB, 108eldm, 80vt, and 87vmax. ADG Brass. Ar2209, ar2213sc, and AR2217. Fed GMM LRPs and Rem 9 1/2. Ive even fed it some factories.
All groups float between 1.2-1.5MOA groups for 8 to 10 shots. Sometimes i can see it wants to group, putting 5 or 6 of the shots into 0.3" then the rest of the group is scattered around it.

Am I being pedantic and this is good enough or have I forgotten something obvious?

Do you have any other platforms that you shoot and get under 1.25”moa with 10rds? How many rounds down the barrel at this point? Try H4350 and N555 powders with the heavier bullets.

 

[mxgsfmdpx]

Consistent 10 shot 1.25 MOA groups?

Go hunt.

You aren’t shooting the difference between a 0.75 MOA gun and a 1.25 MOA gun on animals in the mountains. Unfamiliar terrain, cold shooter, pressure/adrenaline, and being able to call the wind are the great equalizer here.

Pretty sure if someone who has access to one of those 6 degree of freedom fancy probability calculators the difference will be next to nothing in realistic simulated conditions.

All I can attest is, when shooting “1 MOA all day guns” versus “1.5 MOA all day guns” in the mountains 3-5 days per week nearly every week of the year, there is no measurable difference in hit rates on vital sized targets.

 

[wind gypsy]

For all the people saying h4350, ar2209 is the same thing.

 

[SDHNTR]

“DD IBI Medium Hunter barrel”

What is this? Is that a brand? Never heard of them. Prefit? Cut chamber? Button or cut rifling? Inexpensive? What does your smith say about your accuracy expectations?

IMO, you are probably getting all you can expect, especially on a factory action and with an “off brand” or inexpensive (I honestly don’t know) barrel. And your results are definitely good enough. Go hunt.

If you demand more precision you’re probably going to need to spend more money.

 

[TaperPin]

“DD IBI Medium Hunter barrel”

What is this? Is that a brand?

It’s a Canadian company.

Shop - International Barrels

internationalbarrels.com

 

[bonepoint]

Most will say H4350, but my 6 CM definitely preferred RL16 over H4350.

 

[SDHNTR]

It’s a Canadian company.

Shop - International Barrels

internationalbarrels.com

Interesting. Definitely not inexpensive. Button rifled, I see.

OP, are you Canadian? Curious why you chose this barrel manufacturer? Are the better known standards like Bartlein, Brux, Kreiger, Lilja, Benchmark, etc hard to get in Canada?

 

[TaperPin]

Unfortunately even rather expensive custom barrels have a lot of variation and sometimes they are great and sometimes mediocre. My best custom barrel would really shoot and the very next of the same grade from the same place was a 1-1/4 MOA shooter so I remember the disappointment you’re going through well. Many will say just accept it as good enough and in a year you’ll forget about it, but my experience has been it took a decade for the disappointment to fade enough to trust spending that kind of money again. I sold that rifle because every time it was picked up that negative energy was always there.

I’ve picked up some bits of advice over the years from gunsmiths that might change how I would deal with it today, but for the most part the sooner a better barrel replaces it the faster you’ll be happy. Many of the advanced checks aren’t free, so throwing good money at a bad barrel is rarely worth it.

Looking carefully at the crown for burrs with a magnifying lope is low hanging fruit that can be quickly fixed, so it’s worth doing.

Slugging a barrel by a gunsmith is forming a lead slug tightly to the bore and pushing it the full length to feel for tight and loose sections. If the bore loosens up on the muzzle end many gunsmiths have said they won’t look any further, that barrel will never shoot. A threaded muzzle cut with a dull cutter or improper design putting too much pressure in the metal can actually shrink the bore a little, causing problems. Gunsmiths that do this are probably charging at least $150.

Borescoping can sometimes show up a defect in bore or throat, but it would have to be a big/giant obvious defect for the original gunsmith or barrel maker to fix it.

Removing the barrel and dialing in the bore and chamber can find a chamber cut out of alignment, but unless the original gunsmith does it for free, there goes $150, or whatever the going rate is, and having the chamber recut and barrel rethreaded is another $250ish on top of that, but there are no guarantees it will shoot better, so few people come out ahead.

In my case a personal friend loved the idea of having a custom barrel and wasn’t as picky so he bought the barreled action and I bought another receiver to start over.