Blown out primers Hornady 150 FMJBT & Lil Gun

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Tone72885
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Blown out primers Hornady 150 FMJBT & Lil Gun

Post by Tone72885 » Sun Feb 24, 2019 4:09 am

Hi all! New to the forum. Have a buddy who has a 300 blackout. Put some rounds together for him using once fired head stamped 300 blackout brass. Using hornady 150 FMJBT and 15.7 grains of Lil Gun. OAL 2.065. Lab radar has the MV ~2050 ft/sec. Trouble is, they're blowing out the primers about every 4-6 rounds and creating a mess in the gun. What am I missing here? I've searched the forum on load data and it doesn't appear 15.7 grains should be running this hot. Have taken a few apart to double check powder charge and all have been correct. Thanks.

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ThreeHundredBlackout
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by ThreeHundredBlackout » Sun Feb 24, 2019 8:28 am

Check your OAL, hornady 9th says 2.220"

Where did your data come from ?
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dellet
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by dellet » Sun Feb 24, 2019 10:01 am

ThreeHundredBlackout wrote:Check your OAL, hornady 9th says 2.220"

Where did your data come from ?
Speaking of checking your data, loading that bullet to 2.220” would be a mistake. That’s why Hornady issued a correction for the 9th edition. That bullet can be jamming into the lands at that length, it will depend on the chamber.
Page 382, 300 Whisper/AAC Blackout – 150-155gr C.O.L.’s should read: GMX-1.962”, InterBond-2.210”, SST-2.210”, FMJ-BT-2.090”, Interlock RN-1.900”, InterLock SP & BTSP-2.106”, A-MAX-2.110”
https://press.hornady.com/assets/pcthum ... 702177.pdf
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dellet
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by dellet » Sun Feb 24, 2019 10:12 am

Tone72885 wrote:Hi all! New to the forum. Have a buddy who has a 300 blackout. Put some rounds together for him using once fired head stamped 300 blackout brass. Using hornady 150 FMJBT and 15.7 grains of Lil Gun. OAL 2.065. Lab radar has the MV ~2050 ft/sec. Trouble is, they're blowing out the primers about every 4-6 rounds and creating a mess in the gun. What am I missing here? I've searched the forum on load data and it doesn't appear 15.7 grains should be running this hot. Have taken a few apart to double check powder charge and all have been correct. Thanks.
It would be worth checking the chamber and measuring max length for that bulllet and a couple others. It’s possible it has a short throat.

The other possibility is that it’s Lil’gun being Lil’gun. I have rarely been able to get maximum loads without hitting pressure signs. Other people swear by it as a go to powder.

Since you’re getting the predicted velocity of a load that’s 2 grains more, I think it’s safe to believe what the brass is telling you.

Barrel and brass manufacturer would be good to know, as well case capacity for the brass.

May be a lot number for the powder, since this is the second post with pressure problems recently.
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by ThreeHundredBlackout » Sun Feb 24, 2019 11:40 am

dellet wrote:
ThreeHundredBlackout wrote:Check your OAL, hornady 9th says 2.220"

Where did your data come from ?
Speaking of checking your data, loading that bullet to 2.220” would be a mistake. That’s why Hornady issued a correction for the 9th edition. That bullet can be jamming into the lands at that length, it will depend on the chamber.
Page 382, 300 Whisper/AAC Blackout – 150-155gr C.O.L.’s should read: GMX-1.962”, InterBond-2.210”, SST-2.210”, FMJ-BT-2.090”, Interlock RN-1.900”, InterLock SP & BTSP-2.106”, A-MAX-2.110”
https://press.hornady.com/assets/pcthum ... 702177.pdf
Thanks dellet, i didn't see that eratta for the fmj.

( Hodgdon might want to correct their web numbers then also bc they say 2.235" for OAL.) Ofcoarse theirs says hornady interbond but the new errata is alot closer than the fmj was at 2.210 so maybe its ok im not sure as ive never used interbonds.
Last edited by ThreeHundredBlackout on Sun Feb 24, 2019 11:57 am, edited 1 time in total.
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by ThreeHundredBlackout » Sun Feb 24, 2019 11:57 am

It would be nice to know the lilgun lot # for reference.
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by 20X11 » Sun Feb 24, 2019 12:56 pm

What was the temperature when you were shooting? Lil Gun does NOT like to be cold.

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dellet
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by dellet » Sun Feb 24, 2019 1:15 pm

ThreeHundredBlackout wrote:
dellet wrote:
Speaking of checking your data, loading that bullet to 2.220” would be a mistake. That’s why Hornady issued a correction for the 9th edition. That bullet can be jamming into the lands at that length, it will depend on the chamber.



https://press.hornady.com/assets/pcthum ... 702177.pdf
Thanks dellet, i didn't see that eratta for the fmj.

( Hodgdon might want to correct their web numbers then also bc they say 2.235" for OAL.) Ofcoarse theirs says hornady interbond but the new errata is alot closer than the fmj was at 2.210 so maybe its ok im not sure as ive never used interbonds.
Going by the above Hornady info, corrected 9th, the 150 fmj, loaded at 2.090”. Compare it to the Hodgdon data 150 IB @ 2.235” or the Hornady data of 2.210” you need to also compare bullet length.

The 150 IB @ 1.260”, the 150 fmj @ 1.123.

Seated the same depth in the case, the 150 fmj would be 2.098” to match Hospdgdon data.

If you used the Hornady data the same way, IB depth for the Fmj, you would load the Fmj at 2.073”.

For what it’s worth the 150 fmj, will hit the lands in a Sheridan gauge at 2.170”.
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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by Saxon » Sun Feb 24, 2019 2:52 pm

Tone72885 wrote:Hi all! New to the forum. Have a buddy who has a 300 blackout. Put some rounds together for him using once fired head stamped 300 blackout brass. Using hornady 150 FMJBT and 15.7 grains of Lil Gun. OAL 2.065. Lab radar has the MV ~2050 ft/sec. Trouble is, they're blowing out the primers about every 4-6 rounds and creating a mess in the gun. What am I missing here? I've searched the forum on load data and it doesn't appear 15.7 grains should be running this hot. Have taken a few apart to double check powder charge and all have been correct. Thanks.
hornady 9th corrected version also says at 15.7 of lil you should be at 1800 fps so something is off somewhere

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Re: Blown out primers Hornady 150 FMJBT & Lil Gun

Post by TRshootem » Sun Feb 24, 2019 3:32 pm

Hodgdon data shows a OAL of 2.235 for the Hornady 150 IB. 17.2 gr of LilGun is shown as the MAX load at 2062 fps in a 16" barrel. You definitely have something not right in your load!

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