Does the Reamer Pick the Bullet?

[INTJ]

I am a frequent reader but very infrequent poster. I am in my second year back to LR BR after an 11 year gap. After struggling to tune my current 6BRA I got to thinking about reamers and bullets.

As I have gone from the most VLD to the least my rifle has been happier. In order I have tried: 110 SMKs, 105 Berger VLD Targets, 107 SMKs, and 108 Bergers. I'll find out at the match this Sunday if I am tuned, but the Berger 108s finally gave me a round 5-shot group of .32 at 200 yds with an ES of 11 fps. The best group with the 107 SMKs was 9/16" ES 20. The 105 Bergers VLDTs were 11/16" ES 13. The best 110 SMK load was 7/8" ES 8.

So my thought is that the reamer I spec'ed is going to like tangent ogive bullets like the Berger 108 in the barrel I use to cut my next chamber. It's a Manson reamer with a .267 neck, .125 freebore, and a 1.5 degree lead. I guess I could work up a load with my fireforming barrel--I cut it with the same reamer and set up the headspace the same.

Thoughts on the reamer determining the best bullet?

 

[Alex Wheeler]

Not in my experience. If you were playing with throat angles or bore geometry I would say yes. But freebore length, no, so long as it is long enough to not cause issues. 108s are a very accurate bullet with a forgiving seating depth. Many have good luck with that one. The vld is one of the best, but it has a narrow seating window and if your not in it, its not going to shoot. JMO

 

[INTJ]

So the next barrel I chamber with this reamer may like a different bullet?

 

[Alex Wheeler]

Most barrels get along with the 108. Whats your load development procedure?

 

[INTJ]

Ok, so 108s are easy and shoot well in most barrels and as such will not be a good indicator of what I am asking.

So there is not necessarily any correlation between the best bullet for two different barrels cut with the same reamer and set to the same headspace.

Thanks

 

[Alex Wheeler]

If you chamber the same brand of barrel with the same reamer they usually do end up liking similar loads. Thats not the same as the reamer picking the bullet though. As an example, I have about 10 6BRA reamers. The 103 vapor trail shoots well in every one of them thats long enough, it shoots in throated barrels too. Even different designed freebores. But thats in a 4 groove Krieger. Not every barrel will shoot that bullet as well. So, as to why you ended up on the 108, theres a lot of possibilities, but the reamer is way down that list.

 

[INTJ]

Thanks!

 

[gunsandgunsmithing]

I think what you may be seeing is pretty common. That being, the tangent ogive bullets are easier to tune to "very good" accuracy and this is IMO somewhat due to the shape of the bullet and how it mates with a very typical 1.5° leade angle. That said, that does not mean that it's the very best bullet in your barrel. You just often have to search harder to fond the magic of a secant ogive bullet in your barrel, as it is usually a bit more finicky.

So yes, I do think there is something to the reamer design working well with a given bullet but it could just as easily be stated the other way around...that some bullets are easier to tune and to make shoot in more barrels because most do use a 1.5 degree leade. Make sense? Bottom line...a more rounded ogive does seem to be easier to tune but that doesn't mean it shoots better than a well tuned secant or hybrid.

 

[TrxR]

1.5 is 1°30 ? some the robinette 30br reamer is 1°45 how does that effect things?

I know this thread is about 6bra im just curious how the lead angle effects things.

 

[Alex Wheeler]

Yes 1.5 degree is 1 degree 30 minutes. Those short bullets in the 30 br dont have much shank in the neck even on a zero free bore. Going to a steeper throat angle puts more bullet in the neck when you cant shorten the freebore anymore. This is done with the light .22 cal bullets also. Throat angles do have an effect on how a gun shoots, but I believe Robinett used that angle for the reason I mentioned, not to make them shoot better. But I wont speak for him.

 

[dkhunt14]

So the next barrel I chamber with this reamer may like a different bullet?

Ys, it could like a different bullet. I find the VLD's shoot better in the lands with most my barrels. I like the Hunting version verses Target. They seem to be more consistent.

What distance are you going to compete at? What shoots good at 100 and 200 May not shoot good at 600 or 1000 and visa versa. Matt

 

[Nightraider]

Whats your load development procedure?

This

 

[1shot]

In answer to the OP's question, I think the reamer determines what bullet you shoot....sort of. Let me explain. All of my reamers are ground with a short freebore. Then with a setup round with the bullet(s) I plan to shoot, I throat the bbl. accordingly. This has solved several problems for me over the years such as keeping the bullet in front of the donut area in the SLR using Lapua brass, or allowing me to get the maximum amount of powder capacity from a case when a bbl. seems to like a certain bullet, over something I used in the past.
I hope this helps,

Lloyd

 

[Northridge]

does reamer pick bullet? No will handling be slightly different reamer to reamer very possible but a reamer has never held me back with any caliber ever, I have always found success. now bullet to barrel configuration plays a large roll in this relation ship of "tuning a Rifle". if a person attempts 3-4 different bullet designs that are known choices and you can not fine success something drastic needs to change and it will not require a barrel change 99% of the time it is not the barrel but brass prep, charge window or field performance.

Shawn Williams