Can bullet weight alone make a big difference in precision, or powder?

[clearwater]

Shooting a 25-285 with various ballistic tips. With 100 grain BT's and Reloder 17 I can get as small as 1/2" 5 shot groups if I can do my part and deal with my heart beats.

With 115 grain BT's (2nds, but weight sorted) and Reloder 17 or Staball 6.5 or H450, groups are never better than 1 and1/2" for 3 shot groups.
Yesterday I tried some 85 grain BT's with several weights of Reloder 16 and got 1 and 1/2 inch 3 shot groups.

What gives? Can a rifle be that picky of bullet length? Nearly out of Rx17 too. Can't really play with that anymore as I need it for my hunting loads.

Seems like those 85 grain BT's should shoot well. Any powder suggestions? I find the case capacity similar to my 25-06 minus 1 grain.

ALSO Cabela's has the 100 grain BT's on sale. Got 4 boxes yesterday with free ship, minus club discount, plus tax for $64

 

[Aussie Wanderer]

Yep, rifles can be choosy. I have a 338wm that won’t shoot 225sst’s worth a damn, but the same weight AccuBond is a genuine sub moa rifle. My little 7mm08 shoots the cheap interlocks better than any other bullet at the same weight and I have a 9.3x62 that you can feed anything to and it simply just shoots tight groups.

 

[JD338]

Are you referring to the 25-284?

JD338

 

[RL338]

I can honestly say yes. Nosler 260gr E-tip will not cooperate with my 375 Wby. Every bullet otherwise will flat out shoot.

 

[SJB358]

ETips and Sciroccos are the two bullets that either shoot or don’t. No amount of goofing around will make my rifles like them if they don’t show a little promise from the get go.

 

[1100 Remington Man]

My Model 70 300 H&H Mag with Factory loads of Winchester 150gr Silvertips would average 1.5-2.0 inch three shot groups at 100 yards but Winchester 180gr Silvertips were sub MOA. All I reload is 180gr Nosler Partitions or AB but I think I will try some Nosler 180gr BT next, but I will stick with 180gr

 

[PJGunner]

It depends on the rifle I think. I did a lot of work with Ruger #1s and found if one didn't shoot all that well with the commonly used bullet weight, switching to the next heaviest or the heaviest for caliber would usually give a usable group. Most people would use say a 180 gr. bullet for use in the .300 Win. Mag. and the five rifles I have in that chambering do reasonably well with the 180 grain bullet. But, switch to the 200 gr. Speer Hot Core or 200 gr. Nosler Partition and those rifles become very very accurate. Groups run from .375" to .50" with those two bullets compared to 1.0" to 1.25" with the 180 gr. bullet.
I have a load that does an easy .75" in most of my 7x57 rifles with the 150 gr. Nosler except a Rger #1A. Probably 1,25" to 1.5" depending o its mood and time of day. Run anyrhing in 175 gr. and .50" to .8o" is the norm for that one.

I have a 30-06 that will not shoot anytjing accurately if the bullet weighs more that 165 gr. but is easily .50" all day long with the 165 gr. AccuBond.

When I started working up loads for my custom .280 Rem. I started with IMR 7828 SSC. Speed was great but I never got much better tham 2.0 to 2.50" groups. Switched to the lond gone WMR powder and tiny bug hole with the same speed as 7828.

So yes, I think powders and bullets can make a difference.
Paul B.

 

[badaxeriverman]

I can honestly say yes. Nosler 260gr E-tip will not cooperate with my 375 Wby. Every bullet otherwise will flat out shoot.

Solid copper bullets won’t “expand” to fill the bore when you shoot it like a cup and core. Bonded bullets are just as bad imo for not expanding to fill out the “bore”. When fired imo. Have you ever slugged your barrel to measure the inside of it and that E tip? I’ve had some Barnes XLCs that would tumble out my 243 bsck in the day because they were a few thousands under diameter. Just sent some .358 TSSX blue tipped a
Back to Barnes because they were all measuring .357”. My barrel slugged at .358” and I was getting 3 to 6” plus groups with them at a 100 yards. The gun will shoot .4” with cup and core hand loads. Instead of weighing my bullets lately, I’ve been checking the diameters of them. There’s a lot of .358” cup and cores I have in my inventory and various brands that are under sized. Hornadys are .357 and Norma .3565”. Needless to say neither of them group worth a darn either. Speers shoot sub MOA and measure .358/.3585” on average.

 

[salmonchaser]

My Model 70 300 H&H Mag with Factory loads of Winchester 150gr Silvertips would average 1.5-2.0 inch three shot groups at 100 yards but Winchester 180gr Silvertips were sub MOA. All I reload is 180gr Nosler Partitions or AB but I think I will try some Nosler 180gr BT next, but I will stick with 180gr

Hey, I have a box of 180 BT that don’t shoot in my 300HH. Well, half a box anyway, I’ll send them to you.

 

[salmonchaser]

Shooting a 25-285 with various ballistic tips. With 100 grain BT's and Reloder 17 I can get as small as 1/2" 5 shot groups if I can do my part and deal with my heart beats.

With 115 grain BT's (2nds, but weight sorted) and Reloder 17 or Staball 6.5 or H450, groups are never better than 1 and1/2" for 3 shot groups.
Yesterday I tried some 85 grain BT's with several weights of Reloder 16 and got 1 and 1/2 inch 3 shot groups.

What gives? Can a rifle be that picky of bullet length? Nearly out of Rx17 too. Can't really play with that anymore as I need it for my hunting loads.

Seems like those 85 grain BT's should shoot well. Any powder suggestions? I find the case capacity similar to my 25-06 minus 1 grain.

ALSO Cabela's has the 100 grain BT's on sale. Got 4 boxes yesterday with free ship, minus club discount, plus tax for $64

My 257 Roberts is easily the most finicky rifle I own. 100 gr. Ballistic tips are great. 110s are poor and 115s look like I was shooting full choke #4 buck shot.
I’ve tried 4 or 5 powders in the Roberts with 100s all came in at under an inch.
I have an 06 that shoots everything from 130s to 220s quite well. It is well regulated to 150s and 180s. But doesn’t seem to care what powder.
My Moms 257 Roberts was easily the best rifle I’ve ever messed with for consistency. Didn’t matter what you fed it, it shot right at 11/2 groups. Change bullets you never had to adjust windage just correct elevation for the relative speed of the bullets.

 

[RL338]

Solid copper bullets won’t “expand” to fill the bore when you shoot it like a cup and core. Bonded bullets are just as bad imo for not expanding to fill out the “bore”. When fired imo. Have you ever slugged your barrel to measure the inside of it and that E tip?

That rifle flat out shoots 250gr TTSX , 300gr TSX , and 330gr MTH , which are also monos.

 

[badaxeriverman]

Those particular projectiles are probably the same diameter , or a hair larger, as your inner bore dimensions then.


Have you ever slugged your barrel and measured the slug? I normally do with every rifle because I shoot Cast through them. I also measure my jacketed projectiles. Undersized Cup and core projectiles will at least expand when fired to “seal” the bore. Mono projectiles do not. If they are undersized it’s like throwing a hot dog down a hallway and, of course, accuracy is also going to horrible.
Here’s a couple examples I measured in the last few days trying to figure out why my 35 Wasn’t wasn’t grouping worth a darn and throwing pie plate groups at 100 yards. My barrel slugs at .358”. The Speer group I posted here a few days ago at .4” at a 100 yards were with bullets measuring .358”/.3585”. The undersized Norma’s below shot 6 to 12inch groups and the undersized Barnes were on average 3 to 5 inch groups. I did shoot one 1.5” group with the Barnes and figured it was a fluke. I also had 2 Bose of undersized Hornadys. Hornady is going to replace them and Barnes sent a return label to inspect theirs. Norma I’m still waiting to see if they replace them. I had a problem with the 180 grain Speer .358’s years ago. They were .3595” to .363” and crumpling my case necks when trying to seat them in 35 Rem brass. They confirmed the projectiles were way out of spec and replaced them with the ones Im shooting now.

https://imgur.com/y1zGv9B

https://imgur.com/LDd1ONH

I never really started measuring jacketed projectiles till I started having trouble with accuracy in this rifle. I also measured some 180 grain Barnes TSX in 308 that are under sized as well but I didn’t bother messing with sending those in. I’ll save those for another day. Explains why some people have really good luck with mono Boolits and some people do not it’s because the people that do have barrels that are the same size or smaller diameter than mono the projectiles they are using. Unfortunately, manufacturers have a tolerance range of both projectile diameter and internal barrel diameter and if you’re off on either end of the spectrum, you’re gonna suffer an accuracy with a mono bullet. It’s no different than not having the correct size Cast bullet fitment in your barrel. If it’s not exactly the right size accuracy will suffer.


If you have any of those bullets left measure the diameter and then measure the diameters of the ones that shoot good in your gun and see if they vary in diameter.

I normally get an empty shell casing and melt fishing sink if I don’t have pure soft lead and fill up 3/4 of the case. Then I tap it out with my inertia bullet puller. I then tap it through my barrel with a wooden towel and measure the slug… pretty easy process.


Most shooters don’t think outside the box and measure the diameter of their jacketed projectiles… including myself till recently. Been slugging my barrels for the last seven years because I got into cast bullets.