30-30 Velocity Oddities

[Chestnut]

See the bottom of the post for my full setup. My question starts from reloading my 30-30 to a cheap plinking load. I started a ladder 5 shots each with 0.5 grain increments from 28 grains of powder to 29.6. I recorded the velocities but focused on groupings. The Targets indicated that between 28.5 and 29.0 was the sweet spot. Then looking closely at the velocities I was confused.

They were all plus minus 20fps of 2060 and showing a decrease in velocity. Huh? Ok velocity doesn't matter holes matter.

Next I loaded up 5 shots each increasing 0.1 grains between 28.5 and 29.0. Shot over same chrono similar weather conditions. Sweet spot was 28.7 grains resulting in a 1.25" group at 100y, which exceeds my expectations. Looked at the velocities again ran some calcs with excel and made a chart and just got confused. The chart below is at least 5 shot averages with 10 shot averages between 28.5 and 29.0. SDs bounce but are around 10fps



Can any one explain this? Every other load I've developed has had velocity increase as powder charge increases. I researched on this site the last few hours to see if i could find an answer and every velocity chart shows a nice regular expected increase. Some thing is happening because 5 shot groups went from 4-5" at 100y down to 1.25". So despite the velocity staying effectively flat accuracy is being impacted. Ultimately there is no problem I just can't stop thinking about WHY!?

Setup:

Marlin 336BL Chambered in 30-30 win 18" barrel. Don't know twist rate.
Nosler 30-30 Brass (only thing available at the time) trimmed to 2.037 per Mitutoyo calipers. New 2022
Hodgon H335 Powder all from same jug (only thing available at time) New 2022
Hornday 160 grain FTX new 2022
Remington 9 1/2 primers new 2022
Seated to cannelure on bullet and taper crimped per RCBS instructions. Crimp measured around 0.002" per caliper OAL ~2.55
Chrony Chronograph, not sure which model. It's not the chronograph it's worked for other loads shot at the same time. Chronograph was about 7 feet ahead of muzzle.
RCBS Press
RCBS Dies <200 loads
Hornday Digital Scale My scale takes about 5 min to warm up but holds accurate after warmup. Provides accurate charges for many other loads.
RCBS trickler
L.E. Willson Trimmer

 

[ebb]

The only thing that speaks to me is the powder. Its from the worst time in the component shortage. This is based on nothing more than a guess, value it as such. But it sure wouldn't hurt to try a different powder and see if it continues.

 

[gambleone]

Do you have any idea about how many rounds have been thru this barrel?

 

[ebb]

Is this a micro groove rifled barrel? Could that be an issue with this bullet? Have you looked at the bore with a bore scope? I have zero experience with micro groove barrels other than reading that they sometimes have issues with bullets they don't like. I read this on cast bollits so it may be issues with cast bullets, but I would think copper issues would develop faster with smaller grooves than the bigger grooves most barrels use.

 

[K22]

Let me say first that I never loaded for or owned a 30-30. It was my father's deer cartridge of choice, but he shot strictly factory ammo.

I do have a lot of experience with H335, however. Like most ball powders I have used, it has a narrow range of optimum performance meaning slight changes in powder charges can have a measurable effect sometimes creating unexpected results, much more so that extruded powders in my experience. It is one of the reasons I stopped using ball powders many years ago.

Most of the guys that I know that load for the 30-30 used IMR 3031. However, if I obtained 1 1/4 groups at 100 yards with this caliber and rifle, I wouldn't try to fix it.

Also, the case necks on this cartridge are very thin. Possibly crimping consistency could be issue which might create velocity changes.

 

[BigBolt]

I had some of the same issues with my Henry 30/30 some years ago when only shooting hand loads. I purchased a box of MFG ammo, and everything was spot on. So, it was something I was doing during hand loading.

I was not calibrating my scale every 10 or so loads as recommended by the MFGs after warming up. I also use a set of calibration weights and check the scale with them too. When I was sure everything was spot on, I worked up 10 loads. Things got better but there were still some discrepancies in chronograph readings.

I then looked at the factory loads and noticed they all were using a roll crimp, and I was using a taper crimp. So, I broke out my roll crimp die and used the MFG ammo to as a model to set up the roll crimp. What I did find the roll crimp was very slight and I checked the SAAMI specs. which shows a roll crimp.

I then loaded 10 more rounds and found the chronograph readings spot on using LT32 and H4064. I continued on using a rolled crimp and checking my scale and have not had any other issues.

 

[Coyotefurharvester]

What is your headspace, color of the necks?

 

[Todd Earhart]

I tried hard to make the FTX bullet work in my 336. I ended up 150gr RN interlock over 748. Very satisfied with accuracy and FPS.
Todd

 

[wright brothers]

A group of uncrimped, not magazine loaded, but fed one at a time, may show if crimp is a problem.

I will be going down this trail in the future. (crimp) And the 30-30 with H-335 got my attention.

 

[Doom]

Looking at this combination in GRT it seems that H335 and the 30-30 are not a good mix. 29.7 grains grains gives about 2061 fps with 87% Fill and 81% burn in an 18" barrel. The 28 gr is 1956 fps with 82% fill and 78% burn. With those case fill numbers and poor burnout you probably are seeing differences in powder distribution and ignition between cartridges. Your chronograph may also be having issues with unburnt powder at 7 ft (yds?).

A powder along the lines of Benchmark or H322 or maybe Accurate 2230 might give you better results.

 

[Bill K]

How full do the loads fill the case ? Is it possible that the way the powder lies in the case, if there is space between the base of the bullet and powder, could that cause a variation of how the charge is burning and therefore effect the pressure level between cartridges ? Just a thought.

 

[Doom]

How full do the loads fill the case ? Is it possible that the way the powder lies in the case, if there is space between the base of the bullet and powder, could that cause a variation of how the charge is burning and therefore effect the pressure level between cartridges ? Just a thought.

That was precisely my point. How the powder lays in the case can have an effect on the ignition and burning of the powder which is going to affect the pressure and velocity. Is this the case here? I don't know but a higher case fill would be desirable.

It is also an issue that the 30-30 is a low pressure cartridge (42 KSI) and this also affects the burning of the powder. H335 is much happier at 50+ KSI.

 

[Chestnut]

I should have mentioned in my original post that the rifle shoots great with 140 Monoflex and H335. When developing that load velocities stepped up like you'd expect. The sweet spot for 140 mono and H335 is 27.9 grains at 2120 fps.

I have to say i never expected this many responses thanks to everyone. All of your posts have given me something to think about.

Do you have any idea about how many rounds have been thru this barrel?

Not many, I bought it used but it looked like it had hardly ever, maybe never been fired by the previous owners. The loading gate didn't have a single mark on it.

I was not calibrating my scale every 10 or so loads as recommended by the MFGs after warming up. I also use a set of calibration weights and check the scale with them too. When I was sure everything was spot on, I worked up 10 loads. Things got better but there were still some discrepancies in chronograph readings.

I get a bit particular and tend to place a calibration weight on it every other load. The scale works perfectly with this rifle and other loads.

Is this a micro groove rifled barrel? Could that be an issue with this bullet? Have you looked at the bore with a bore scope? I have zero experience with micro groove barrels other than reading that they sometimes have issues with bullets they don't like. I read this on cast bollits so it may be issues with cast bullets, but I would think copper issues would develop faster with smaller grooves than the bigger grooves most barrels use.

Yes micro groove stamped on the barrel. Maybe an issue with the bullet but I'm getting accurate groups so it's hard to say yes defiantly. I have not looked at the bore.

It is one of the reasons I stopped using ball powders many years ago.

I find this comment interesting especially with the new Staball powders Hogdon made. I've been shooting the Staball 6.5 out of my 6.5CM and it has been yielding excellent results so far.

What is your headspace, color of the necks?

No idea on the headspace. Neck color of the factor brass was shiny brass just like the the rest of the case. After firing the necks all have some burned powder residue on them back to the shoulder.

I tried hard to make the FTX bullet work in my 336. I ended up 150gr RN interlock over 748. Very satisfied with accuracy and FPS.
Todd

The 140 Mono shoots a bit better in my rifle as well and is what i actually use for deer hunting.

Looking at this combination in GRT it seems that H335 and the 30-30 are not a good mix. 29.7 grains grains gives about 2061 fps with 87% Fill and 81% burn in an 18" barrel. The 28 gr is 1956 fps with 82% fill and 78% burn. With those case fill numbers and poor burnout you probably are seeing differences in powder distribution and ignition between cartridges. Your chronograph may also be having issues with unburnt powder at 7 ft (yds?).

A powder along the lines of Benchmark or H322 or maybe Accurate 2230 might give you better results.

Question. Would i see a pretty good muzzle flash? I just bought a Garmin Zero so I'm going to shoot this load with that chrono and see if there is a difference. This is wholly a problem of powder available at the time. Once I'm done with this 8lbs of H335 I'll shoot a different powder. At the rate I shoot it might end up being my unborn son that will have to take that on.

It is also an issue that the 30-30 is a low pressure cartridge (42 KSI) and this also affects the burning of the powder. H335 is much happier at 50+ KSI.

Would it help to shoot magnum primers and drop back on powder a bit? Or would that just exacerbate the case fill issue?

How full do the loads fill the case ? Is it possible that the way the powder lies in the case, if there is space between the base of the bullet and powder, could that cause a variation of how the charge is burning and therefore effect the pressure level between cartridges ? Just a thought.

That was precisely my point. How the powder lays in the case can have an effect on the ignition and burning of the powder which is going to affect the pressure and velocity. Is this the case here? I don't know but a higher case fill would be desirable.

It is also an issue that the 30-30 is a low pressure cartridge (42 KSI) and this also affects the burning of the powder. H335 is much happier at 50+ KSI.

Bill and Doom it's interesting that you say that. The other load that stepped up completely as expected in velocity was using the 140 Monoflex bullet and H335 but with less fill. The sweet spot ended up at 27.9 grains.

So would shooting angle then impact how the gun shoots? If I'm say hanging from a tree about 25 feet up and shooting down at a 15 degree angle?

 

[Todd Earhart]

Are you using Hornady load data? Using the FTX bullet all powders other than LVR have a low case fill with the FTX. I don't care for a low case fill and the reason of me going with the 748. I suppose the bearing surface of the FTX bullet has a effect on load data over more conventional bullets used for the caliber. I was never able to achieve the accuracy I wanted with the FTX but I was also looking for more velocity. I'm very satisfied with the interlocks and 748. 2350 fps and 1 inch at 100.
Todd

 

[Bill K]

Would it help to shoot magnum primers and drop back on powder a bit? Or would that just exacerbate the case fill issue?


Bill and Doom it's interesting that you say that. The other load that stepped up completely as expected in velocity was using the 140 Monoflex bullet and H335 but with less fill. The sweet spot ended up at 27.9 grains.

So would shooting angle then impact how the gun shoots? If I'm say hanging from a tree about 25 feet up and shooting down at a 15 degree angle?

I think it could. If you have space between bullet base and powder, how about trying some filler to hold powder down against the primer/base of cartridge and see if your loads don't level off. Small amount of tissue or kapoc might be worth a try.

 

[K22]

I find this comment interesting especially with the new Staball powders Hogdon made. I've been shooting the Staball 6.5 out of my 6.5CM and it has been yielding excellent results so far.

H335 and H380 (ball powders) also shot very well in my 223 Rem and 22 250 respectively once I found a load. The problems I had with them were due to temperature changes. One of the issues I had, more so with H380 was pressure surges in 90+ degree weather in the field. Also there seemed to be a narrower range of powders charges that grouped well when compared to extruded powders. Had the same issue with BL C2 in the 222 Rem.

However, I am a great advocate of not fixing something that isn't broken, so if you are obtaining excellent results with your current powder then by all means stay with it. Also, maybe the formulation of Staball is different than BLC2, H335 and H380 nullifying the issue I had with the aformentioned ball powders.

 

[pintopete]

Chestnut, did you choose H335 because it is an appropriate powder that you have on hand, or for the velocity? I can understand choosing one that is at the top velocities for hunting. Do you have any H4895, Varget or LeveRevolution powder? You might consider trying one of those.
Stuff you may already know…on your rest, make sure you support the forend the same every time. I would have the front rest where my weak hand would be.
Believe it or not, some people don’t crimp lever rounds. Not sure about that. When making changes, change only one thing at a time. Otherwise you can’t be sure which it was.
I think you said you were plinking, not necessarily hunting at this point. Maybe Speer 130’s for fun shooting? Some 30/30 fans say they get best accuracy and terminal performance on deer with conventional 170gr bullets. There are also 150gr conventional RN that are available now.
Sorry if I’m being Captain Obvious. I hope to find the time to do what you are doing soon. FWIW, in my 35 Rem, factory Winchester 150gr ammo is very noticeably more accurate than the factory LeveRevolution ammo. Very different combo than yours, but food for thought.

Best of luck, Peter.

 

[Doom]

Question. Would i see a pretty good muzzle flash? I just bought a Garmin Zero so I'm going to shoot this load with that chrono and see if there is a difference. This is wholly a problem of powder available at the time. Once I'm done with this 8lbs of H335 I'll shoot a different powder. At the rate I shoot it might end up being my unborn son that will have to take that on.

I haven't messed with H335 in over 10 years and only in a 26" 223 so I don't know for sure But would expect you will.

Would it help to shoot magnum primers and drop back on powder a bit? Or would that just exacerbate the case fill issue?

It might. Only test would tell.

Looking at your velocity data if your chronograph is only 7 ft away your data is likely being influenced by muzzle blast. Obviously the Garmin will not have that issue.

A note on LeverEvolution. Hornady noted that the FTX was used in the Ammunition that introduced that bullet and the powder was LeverEvolution. That powder gives >95% case fill.

AS for angles and powder, the best way to see if case fill is having an impact is to load six to ten cartridges and place them in the ammo box 3 or 5 bullets up and 3 or 5 bullets down. Single load each one and fire over the chronograph being careful to not change the location of the powder. Look for velocity and POI changes.

 

[Chestnut]

Are you using Hornady load data? Using the FTX bullet all powders other than LVR have a low case fill with the FTX. I don't care for a low case fill and the reason of me going with the 748. I suppose the bearing surface of the FTX bullet has a effect on load data over more conventional bullets used for the caliber. I was never able to achieve the accuracy I wanted with the FTX but I was also looking for more velocity. I'm very satisfied with the interlocks and 748. 2350 fps and 1 inch at 100.
Todd

Yes i am using hornady load data. According to the load data I'm on the upper end of the velocities i should expect with H335. I have bought some LVR powder since and I'll be experimenting with that. The interesting part to me is that lever powder burns slower than H335 according to Hodgon burn chart.

I think it could. If you have space between bullet base and powder, how about trying some filler to hold powder down against the primer/base of cartridge and see if your loads don't level off. Small amount of tissue or kapoc might be worth a try.

Interesting thought, I suppose i was happy with 1.25" groups but if better can be achieved why not?

 

[Chestnut]

Chestnut, did you choose H335 because it is an appropriate powder that you have on hand, or for the velocity?

I bought the 30-30 early 2022 and of the 12 powders listed for the load data i had this was the only one in stock. I had a strong desire to not carry my 270WSM for another hunting season so i just went with it. At the time all I had for powder was IMR 4350 and Green Dot. If i could do it all over again with every powder that's in stock now I woulnd't have 8lbs of H335. Literally the only jug aviable I had load data for at the time. If anyone remembers there wasn't a single box of ammo on the shelf at that time let alone the more oddball stuff like 30-30.

Do you have any H4895, Varget or LeveRevolution powder? You might consider trying one of those.

I have LVR powder now and am toying with it. My goal is to get the 140 monoflex velocities up from my gun before I start with the 160 ftx though as the 140 will be my main hunting round.

Stuff you may already know…on your rest, make sure you support the forend the same every time. I would have the front rest where my weak hand would be.
Believe it or not, some people don’t crimp lever rounds. Not sure about that. When making changes, change only one thing at a time. Otherwise you can’t be sure which it was.
I think you said you were plinking, not necessarily hunting at this point. Maybe Speer 130’s for fun shooting? Some 30/30 fans say they get best accuracy and terminal performance on deer with conventional 170gr bullets. There are also 150gr conventional RN that are available now.
Sorry if I’m being Captain Obvious. I hope to find the time to do what you are doing soon. FWIW, in my 35 Rem, factory Winchester 150gr ammo is very noticeably more accurate than the factory LeveRevolution ammo. Very different combo than yours, but food for thought.

Yes I try and be dilligant on resting the gun the same way. Additionally,I try to hold the gun at the bench the same way I'd rest it if hunting. All of this is just trying to make my gun shoot well. The last deer i shot was 27 feet from my tree so a 1.25" group is going to get the job done. Heck a 4" group would be good enough at that range.

Really some people don't crimp lever rounds? Wouldn't that cause bullet compression? Isn't there a proper term for where the bullet gets pushed into the brass?

I"m mostly just buying components that are on the shelf at stores in my area. Up untill recently the 2 hornady level bullets were all I could find. I have a few boxes of each so i'm shooting them before I try more. Since ammo has become avilable I've tried every factor load from my gun. I don't know what it is with my rifle but the only factory ammo that shoots worth a dang is the 160 hornadys. 150 round noses and 170 round nose from the vista outdoor collection struggled to get 5" groups at 50y...... I don't know why the stores around here don't stock round nose but i don't see them on shelves.